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     element.
    
     The title should identify the contents of the document in a global
     context. A short title, such as "Introduction" may be meaningless out
     of context. A title such as "Introduction to HTML Elements" is more
     appropriate.
    
      NOTE - The length of a title is not limited; however, long titles
      may be truncated in some applications. To minimize this
      possibility, titles should be fewer than 64 characters.
    
     A user agent may display the title of a document in a history list or
     as a label for the window displaying the document. This differs from
     headings (5.4, "Headings: H1 ... H6"), which are typically displayed
     within the body text flow.
    
    5.2.2. Base Address: BASE
    
     The optional &lt;BASE&gt; element provides a base address for interpreting
     relative URLs when the document is read out of context (see 7,
     "Hyperlinks"). The value of the HREF attribute must be an absolute
     URI.
    
    5.2.3. Keyword Index: ISINDEX
    
     The &lt;ISINDEX&gt; element indicates that the user agent should allow the
     user to search an index by giving keywords. See 7.5, "Queries and
     Indexes" for details.
    
    
    
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    5.2.4. Link: LINK
    
     The &lt;LINK&gt; element represents a hyperlink (see 7, "Hyperlinks").  Any
     number of LINK elements may occur in the &lt;HEAD&gt; element of an HTML
     document. It has the same attributes as the &lt;A&gt; element (see 5.7.3,
     "Anchor: A").
    
     The &lt;LINK&gt; element is typically used to indicate authorship, related
     indexes and glossaries, older or more recent versions, document
     hierarchy, associated resources such as style sheets, etc.
    
    5.2.5. Associated Meta-information: META
    
     The &lt;META&gt; element is an extensible container for use in identifying
     specialized document meta-information.  Meta-information has two main
     functions:
    
      * to provide a means to discover that the data set exists
      and how it might be obtained or accessed; and
    
      * to document the content, quality, and features of a data
      set, indicating its fitness for use.
    
     Each &lt;META&gt; element specifies a name/value pair. If multiple META
     elements are provided with the same name, their combined contents--
     concatenated as a comma-separated list--is the value associated with
     that name.
    
      NOTE - The &lt;META&gt; element should not be used where a
      specific element, such as &lt;TITLE&gt;, would be more
      appropriate. Rather than a &lt;META&gt; element with a URI as
      the value of the CONTENT attribute, use a &lt;LINK&gt;
      element.
    
     HTTP servers may read the content of the document &lt;HEAD&gt; to generate
     header fields corresponding to any elements defining a value for the
     attribute HTTP-EQUIV.
    
      NOTE - The method by which the server extracts document
      meta-information is unspecified and not mandatory. The
      &lt;META&gt; element only provides an extensible mechanism for
      identifying and embedding document meta-information --
      how it may be used is up to the individual server
      implementation and the HTML user agent.
    
    
    
    
    
    
    
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    Attributes of the META element:
    
    HTTP-EQUIV
       binds the element to an HTTP header field. An HTTP
       server may use this information to process the document.
       In particular, it may include a header field in the
       responses to requests for this document: the header name
       is taken from the HTTP-EQUIV attribute value, and the
       header value is taken from the value of the CONTENT
       attribute. HTTP header names are not case sensitive.
    
    NAME
       specifies the name of the name/value pair. If not
       present, HTTP-EQUIV gives the name.
    
    CONTENT
       specifies the value of the name/value pair.
    
    Examples
    
    If the document contains:
    
    &lt;META HTTP-EQUIV="Expires"
       CONTENT="Tue, 04 Dec 1993 21:29:02 GMT"&gt;
    &lt;meta http-equiv="Keywords" CONTENT="Fred"&gt;
    &lt;META HTTP-EQUIV="Reply-to"
       content="fielding@ics.uci.edu (Roy Fielding)"&gt;
    &lt;Meta Http-equiv="Keywords" CONTENT="Barney"&gt;
    
    then the server may include the following header fields:
    
    Expires: Tue, 04 Dec 1993 21:29:02 GMT
    Keywords: Fred, Barney
    Reply-to: fielding@ics.uci.edu (Roy Fielding)
    
    as part of the HTTP response to a `GET' or `HEAD' request for
    that document.
    
    An HTTP server must not use the &lt;META&gt; element to form an HTTP
    response header unless the HTTP-EQUIV attribute is present.
    
    An HTTP server may disregard any &lt;META&gt; elements that specify
    information controlled by the HTTP server, for example `Server',
    
    `Date', and `Last-modified'.
    
    
    
    
    
    
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    5.2.6. Next Id: NEXTID
    
     The &lt;NEXTID&gt; element is included for historical reasons only.  HTML
     documents should not contain &lt;NEXTID&gt; elements.
    
     The &lt;NEXTID&gt; element gives a hint for the name to use for a new &lt;A&gt;
     element when editing an HTML document. It should be distinct from all
     NAME attribute values on &lt;A&gt; elements. For example:
    
     &lt;NEXTID N=Z27&gt;
    
    5.3. Body: BODY
    
     The &lt;BODY&gt; element contains the text flow of the document, including
     headings, paragraphs, lists, etc.
    
     For example:
    
    &lt;BODY&gt;
    &lt;h1&gt;Important Stuff&lt;/h1&gt;
    &lt;p&gt;Explanation about important stuff...
    &lt;/BODY&gt;
    
    5.4. Headings: H1 ... H6
    
     The six heading elements, &lt;H1&gt; through &lt;H6&gt;, denote section headings.
     Although the order and occurrence of headings is not constrained by
     the HTML DTD, documents should not skip levels (for example, from H1
     to H3), as converting such documents to other representations is
     often problematic.
    
     Example of use:
    
    &lt;H1&gt;This is a heading&lt;/H1&gt;
    Here is some text
    &lt;H2&gt;Second level heading&lt;/H2&gt;
    Here is some more text.
    
    Typical renderings are:
    
    H1
       Bold, very-large font, centered. One or two blank lines
       above and below.
    
    H2
       Bold, large font, flush-left. One or two blank lines
       above and below.
    
    
    
    
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    H3
       Italic, large font, slightly indented from the left
       margin. One or two blank lines above and below.
    
    H4
       Bold, normal font, indented more than H3. One blank line
       above and below.
    
    H5
       Italic, normal font, indented as H4. One blank line
       above.
    
    H6
       Bold, indented same as normal text, more than H5. One
       blank line above.
    
    5.5. Block Structuring Elements
    
     Block structuring elements include paragraphs, lists, and block
     quotes. They must not contain heading elements, but they may contain
     phrase markup, and in some cases, they may be nested.
    
    5.5.1. Paragraph: P
    
     The &lt;P&gt; element indicates a paragraph. The exact indentation, leading
     space, etc. of a paragraph is not specified and may be a function of
     other tags, style sheets, etc.
    
     Typically, paragraphs are surrounded by a vertical space of one line
     or half a line. The first line in a paragraph is indented in some
     cases.
    
     Example of use:
    
    &lt;H1&gt;This Heading Precedes the Paragraph&lt;/H1&gt;
    &lt;P&gt;This is the text of the first paragraph.
    &lt;P&gt;This is the text of the second paragraph. Although you do not
    need to start paragraphs on new lines, maintaining this
    convention facilitates document maintenance.&lt;/P&gt;
    &lt;P&gt;This is the text of a third paragraph.&lt;/P&gt;
    
    5.5.2. Preformatted Text: PRE
    
     The &lt;PRE&gt; element represents a character cell block of text and is
     suitable for text that has been formatted for a monospaced font.
    
     The &lt;PRE&gt; tag may be used with the optional WIDTH attribute. The
     WIDTH attribute specifies the maximum number of characters for a line
    
    
    
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     and allows the HTML user agent to select a suitable font and
     indentation.
    
     Within preformatted text:
    
      * Line breaks within the text are rendered as a move to the
      beginning of the next line.
    
       NOTE - References to the "beginning of a new line"
       do not imply that the renderer is forbidden from
       using a constant left indent for rendering
       preformatted text. The left indent may be
       constrained by the width required.
    
      * Anchor elements and phrase markup may be used.
    
       NOTE - Constraints on the processing of &lt;PRE&gt;
       content may limit or prevent the ability of the HTML
       user agent to faithfully render phrase markup.
    
      * Elements that define paragraph formatting (headings,
      address, etc.) must not be used.
    
       NOTE - Some historical documents contain &lt;P&gt; tags in
       &lt;PRE&gt; elements. User agents are encouraged to treat
       this as a line break. A &lt;P&gt; tag followed by a
       newline character should produce only one line
       break, not a line break plus a blank line.
    
      * The horizontal tab character (code position 9 in the HTML
      document character set) must be interpreted as the smallest
      positive nonzero number of spaces which will leave the
      number of characters so far on the line as a multiple of 8.
      Documents should not contain tab characters, as they are not
      supported consistently.
    
    Example of use:
    
    &lt;PRE&gt;
    Line 1.
        Line 2 is to the right of line 1.     &lt;a href="abc"&gt;abc&lt;/a&gt;
        Line 3 aligns with line 2.            &lt;a href="def"&gt;def&lt;/a&gt;
    &lt;/PRE&gt;
    
    
    
    
    
    
    
    
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    5.5.2.1. Example and Listing: XMP, LISTING
    
     The &lt;XMP&gt; and &lt;LISTING&gt; elements are similar to the &lt;PRE&gt; element,
     but they have a different syntax. Their content is declared as CDATA,
     which means that no markup except the end-tag open delimiter-in-
     context is recognized (see 9.6 "Delimiter Recognition" of [SGML]).
    
      NOTE - In a previous draft of the HTML specification, the syntax
      of &lt;XMP&gt; and &lt;LISTING&gt; elements allowed closing tags to be treated
      as data characters, as long as the tag name was not &lt;XMP&gt; or
      &lt;LISTING&gt;, respectively.
    
     Since CDATA declared content has a number of unfortunate interactions
     with processing techniques and tends to be used and implemented
     inconsistently, HTML documents should not contain &lt;XMP&gt; nor &lt;LISTING&gt;
     elements -- the &lt;PRE&gt; tag is more expressive and more consistently
     supported.
    
     The &lt;LISTING&gt; element should be rendered so that at least 132
     characters fit on a line. The &lt;XMP&gt; element should be rendered so
     that at least 80 characters fit on a line but is otherwise identical
     to the &lt;LISTING&gt; element.
    
      NOTE - In a previous draft, HTML included a &lt;PLAINTEXT&gt; element
      that is similar to the &lt;LISTING&gt; element, except that there is no
      closing tag: all characters after the &lt;PLAINTEXT&gt; start-tag are
      data.
    
    5.5.3. Address: ADDRESS
    
     The &lt;ADDRESS&gt; element contains such information as address, signature
     and authorship, often at the beginning or end of the body of a
     document.
    
     Typically, the &lt;ADDRESS&gt; element is rendered in an italic typeface
     and may be indented.
    
     Example of use:
    
    &lt;ADDRESS&gt;
    Newsletter editor&lt;BR&gt;
    J.R. Brown&lt;BR&gt;
    JimquickPost News, Jimquick, CT 01234&lt;BR&gt;
    Tel (123) 456 7890
    &lt;/ADDRESS&gt;
    
    
    
    
    
    
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    5.5.4. Block Quote: BLOCKQUOTE
    
     The &lt;BLOCKQUOTE&gt; element contains text quoted from another source.
    
     A typical rendering might be a slight extra left and right indent,
     and/or italic font. The &lt;BLOCKQUOTE&gt; typically provides space above
     and below the quote.
    
     Single-font rendition may reflect the quotation style of Internet
     mail by putting a vertical line of graphic characters, such as the
     greater than symbol (&gt;), in the left margin.
    
     Example of use:
    
    I think the play ends
    &lt;BLOCKQUOTE&gt;
    &lt;P&gt;Soft you now, the fair Ophelia. Nymph, in thy orisons, be all
    my sins remembered.
    &lt;/BLOCKQUOTE&gt;
    but I am not sure.
    
    5.6. List Elements
    
     HTML includes a number of list elements. They may be used in
     combination; for example, a &lt;OL&gt; may be nested in an &lt;LI&gt; element of
     a &lt;UL&gt;.
    
     The COMPACT attribute suggests that a compact rendering be used.
    
    5.6.1. Unordered List: UL, LI
    
     The &lt;UL&gt; represents a list of items -- typically rendered as a
     bulleted list.
    
     The content of a &lt;UL&gt; element is a sequence of &lt;LI&gt; elements.  For
     example:
    
    &lt;UL&gt;
    &lt;LI&gt;First list item
    &lt;LI&gt;Second list item
     &lt;p&gt;second paragraph of second item
    &lt;LI&gt;Third list item
    &lt;/UL&gt;
    
    5.6.2. Ordered List: OL
    
     The &lt;OL&gt; element represents an ordered list of items, sorted by
     sequence or order of importance. It is typically rendered as a
    
    
    
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     numbered list.
    
     The content of a &lt;OL&gt; element is a sequence of &lt;LI&gt; elements.  For
     example:
    
    &lt;OL&gt;
    &lt;LI&gt;Click the Web button to open URI window.
    &lt;LI&gt;Enter the URI number in the text field of the Open URI
    window. The Web document you specified is displayed.
      &lt;ol&gt;
       &lt;li&gt;substep 1
       &lt;li&gt;substep 2
      &lt;/ol&gt;
    &lt;LI&gt;Click highlighted text to move from one link to another.
    &lt;/OL&gt;
    
    5.6.3. Directory List: DIR
    
     The &lt;DIR&gt; element is similar to the &lt;UL&gt; element. It represents a
     list of short items, typically up to 20 characters each. Items in a
     directory list may be arranged in columns, typically 24 characters
     wide.
    
     The content of a &lt;DIR&gt; element is a sequence of &lt;LI&gt; elements.
     Nested block elements are not allowed in the content of &lt;DIR&gt;
     elements. For example:
    
    &lt;DIR&gt;
    &lt;LI&gt;A-H&lt;LI&gt;I-M
    &lt;LI&gt;M-R&lt;LI&gt;S-Z
    &lt;/DIR&gt;
    
    5.6.4. Menu List: MENU
    
     The &lt;MENU&gt; element is a list of items with typically one line per
     item. The menu list style is typically more compact than the style of
     an unordered list.
    
     The content of a &lt;MENU&gt; element is a sequence of &lt;LI&gt; elements.
     Nested block elements are not allowed in the content of &lt;MENU&gt;
     elements. For example:
    
    &lt;MENU&gt;
    &lt;LI&gt;First item in the list.
    &lt;LI&gt;Second item in the list.
    &lt;LI&gt;Third item in the list.
    &lt;/MENU&gt;
    
    
    
    
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    5.6.5. Definition List: DL, DT, DD
    
     A definition list is a list of terms and corresponding definitions.
     Definition lists are typically formatted with the term flush-left and
     the definition, formatted paragraph style, indented after the term.
    
     The content of a &lt;DL&gt; element is a sequence of &lt;DT&gt; elements and/or
     &lt;DD&gt; elements, usually in pairs. Multiple &lt;DT&gt; may be paired with a
     single &lt;DD&gt; element. Documents should not contain multiple
     consecutive &lt;DD&gt; elements.
    
     Example of use:
    
    &lt;DL&gt;
    &lt;DT&gt;Term&lt;DD&gt;This is the definition of the first term.
    &lt;DT&gt;Term&lt;DD&gt;This is the definition of the second term.
    &lt;/DL&gt;
    
     If the DT term does not fit in the DT column (typically one third of
     the display area), it may be extended across the page with the DD
     section moved to the next line, or it may be wrapped onto successive
     lines of the left hand column.
    
     The optional COMPACT attribute suggests that a compact rendering be
     used, because the list items are small and/or the entire list is
     large.
    
     Unless the COMPACT attribute is present, an HTML user agent may leave
     white space between successive DT, DD pairs. The COMPACT attribute
     may also reduce the width of the left-hand (DT) column.
    
    &lt;DL COMPACT&gt;
    &lt;DT&gt;Term&lt;DD&gt;This is the first definition in compact format.
    &lt;DT&gt;Term&lt;DD&gt;This is the second definition in compact format.
    &lt;/DL&gt;
    
    5.7. Phrase Markup
    
     Phrases may be marked up according to idiomatic usage, typographic
     appearance, or for use as hyperlink anchors.
    
     User agents must render highlighted phrases distinctly from plain
     text. Additionally, &lt;EM&gt; content must be rendered as distinct from
     &lt;STRONG&gt; content, and &lt;B&gt; content must rendered as distinct from &lt;I&gt;
     content.
    
     Phrase elements may be nested within the content of other phrase
     elements; however, HTML user agents may render nested phrase elements
    
    
    
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     indistinctly from non-nested elements:
    
     plain &lt;B&gt;bold &lt;I&gt;italic&lt;/I&gt;&lt;/B&gt; may be rendered
     the same as plain &lt;B&gt;bold &lt;/B&gt;&lt;I&gt;italic&lt;/I&gt;
    
    5.7.1. Idiomatic Elements
    
     Phrases may be marked up to indicate certain idioms.
    
      NOTE - User agents may support the &lt;DFN&gt; element, not included in
      this specification, as it has been deployed to some extent. It is
      used to indicate the defining instance of a term, and it is
      typically rendered in italic or bold italic.
    
    5.7.1.1. Citation: CITE
    
      The &lt;CITE&gt; element is used to indicate the title of a book or
      other citation. It is typically rendered as italics. For example:
    
      He just couldn't get enough of &lt;cite&gt;The Grapes of Wrath&lt;/cite&gt;.
    
    5.7.1.2. Code: CODE
    
      The &lt;CODE&gt; element indicates an example of code, typically
      rendered in a mono-spaced font. The &lt;CODE&gt; element is intended for
      short words or phrases of code; the &lt;PRE&gt; block structuring
      element (5.5.2, "Preformatted Text: PRE") is more appropriate
       for multiple-line listings. For example:
    
      The expression &lt;code&gt;x += 1&lt;/code&gt;
      is short for &lt;code&gt;x = x + 1&lt;/code&gt;.
    
    5.7.1.3. Emphasis: EM
    
      The &lt;EM&gt; element indicates an emphasized phrase, typically
      rendered as italics. For example:
    
      A singular subject &lt;em&gt;always&lt;/em&gt; takes a singular verb.
    
    5.7.1.4. Keyboard: KBD
    
      The &lt;KBD&gt; element indicates text typed by a user, typically
      rendered in a mono-spaced font. This is commonly used in
      instruction manuals. For example:
    
      Enter &lt;kbd&gt;FIND IT&lt;/kbd&gt; to search the database.
    
    
    
    
    
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    5.7.1.5. Sample: SAMP
    
      The &lt;SAMP&gt; element indicates a sequence of literal characters,
      typically rendered in a mono-spaced font. For example:
    
      The only word containing the letters &lt;samp&gt;mt&lt;/samp&gt; is dreamt.
    
    5.7.1.6. Strong Emphasis: STRONG
    
      The &lt;STRONG&gt; element indicates strong emphasis, typically rendered
      in bold. For example:
    
      &lt;strong&gt;STOP&lt;/strong&gt;, or I'll say "&lt;strong&gt;STOP&lt;/strong&gt;" again!
    
    5.7.1.7. Variable: VAR
    
      The &lt;VAR&gt; element indicates a placeholder variable, typically
      rendered as italic. For example:
    
      Type &lt;SAMP&gt;html-check &lt;VAR&gt;file&lt;/VAR&gt; | more&lt;/SAMP&gt;
      to check &lt;VAR&gt;file&lt;/VAR&gt; for markup errors.
    
    5.7.2. Typographic Elements
    
      Typographic elements are used to specify the format of marked
      text.
    
      Typical renderings for idiomatic elements may vary between user
      agents. If a specific rendering is necessary -- for example, when
      referring to a specific text attribute as in "The italic parts are
      mandatory" -- a typographic element can be used to ensure that the
      intended typography is used where possible.
    
      NOTE - User agents may support some typographic elements not
      included in this specification, as they have been deployed to some
      extent. The &lt;STRIKE&gt; element indicates horizontal line through the
      characters, and the &lt;U&gt; element indicates an underline.
    
    5.7.2.1. Bold: B
    
     The &lt;B&gt; element indicates bold text. Where bold typography is
     unavailable, an alternative representation may be used.
    
    5.7.2.2. Italic: I
    
     The &lt;I&gt; element indicates italic text. Where italic typography is
     unavailable, an alternative representation may be used.
    
    
    
    
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    5.7.2.3. Teletype: TT
    
     The &lt;TT&gt; element indicates teletype (monospaced )text. Where a
     teletype font is unavailable, an alternative representation may be
     used.
    
    5.7.3. Anchor: A
    
     The &lt;A&gt; element indicates a hyperlink anchor (see 7, "Hyperlinks").
     At least one of the NAME and HREF attributes should be present.
     Attributes of the &lt;A&gt; element:
    
    HREF
       gives the URI of the head anchor of a hyperlink.
    
    NAME
       gives the name of the anchor, and makes it available as
       a head of a hyperlink.
    
    TITLE
       suggests a title for the destination resource --
       advisory only. The TITLE attribute may be used:
    
       * for display prior to accessing the destination
       resource, for example, as a margin note or on a
       small box while the mouse is over the anchor, or
       while the document is being loaded;
    
       * for resources that do not include a title, such as
       graphics, plain text and Gopher menus, for use as a
       window title.
    
    REL
       The REL attribute gives the relationship(s) described by
       the hyperlink. The value is a whitespace separated list
       of relationship names. The semantics of link
       relationships are not specified in this document.
    
    REV
       same as the REL attribute, but the semantics of the
       relationship are in the reverse direction. A link from A
       to B with REL="X" expresses the same relationship as a
       link from B to A with REV="X". An anchor may have both
       REL and REV attributes.
    
    URN
       specifies a preferred, more persistent identifier for
       the head anchor of the hyperlink. The syntax and
    
    
    
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       semantics of the URN attribute are not yet specified.
    
    METHODS
       specifies methods to be used in accessing the
       destination, as a whitespace-separated list of names.
       The set of applicable names is a function of the scheme
       of the URI in the HREF attribute. For similar reasons as
       for the TITLE attribute, it may be useful to include the
       information in advance in the link. For example, the
       HTML user agent may chose a different rendering as a
       function of the methods allowed; for example, something
       that is searchable may get a different icon.
    
    5.8. Line Break: BR
    
     The &lt;BR&gt; element specifies a line break between words (see 6,
     "Characters, Words, and Paragraphs"). For example:
    
    &lt;P&gt; Pease porridge hot&lt;BR&gt;
    Pease porridge cold&lt;BR&gt;
    Pease porridge in the pot&lt;BR&gt;
    Nine days old.
    
    5.9. Horizontal Rule: HR
    
     The &lt;HR&gt; element is a divider between sections of text; typically a
     full width horizontal rule or equivalent graphic.  For example:
    
    &lt;HR&gt;
    &lt;ADDRESS&gt;February 8, 1995, CERN&lt;/ADDRESS&gt;
    &lt;/BODY&gt;
    
    5.10. Image: IMG
    
     The &lt;IMG&gt; element refers to an image or icon via a hyperlink (see
     7.3, "Simultaneous Presentation of Image Resources").
    
     HTML user agents may process the value of the ALT attribute as an
     alternative to processing the image resource indicated by the SRC
     attribute.
    
      NOTE - Some HTML user agents can process graphics linked via
      anchors, but not &lt;IMG&gt; graphics. If a graphic is essential, it
      should be referenced from an &lt;A&gt; element rather than an &lt;IMG&gt;
      element. If the graphic is not essential, then the &lt;IMG&gt; element
      is appropriate.
    
     Attributes of the &lt;IMG&gt; element:
    
    
    
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    ALIGN
       alignment of the image with respect to the text
       baseline.
    
       * `TOP' specifies that the top of the image aligns
       with the tallest item on the line containing the
       image.
    
       * `MIDDLE' specifies that the center of the image
       aligns with the baseline of the line containing the
       image.
    
       * `BOTTOM' specifies that the bottom of the image
       aligns with the baseline of the line containing the
       image.
    
    ALT
       text to use in place of the referenced image resource,
       for example due to processing constraints or user
       preference.
    
    ISMAP
       indicates an image map (see 7.6, "Image Maps").
    
    SRC
       specifies the URI of the image resource.
    
       NOTE - In practice, the media types of image
       resources are limited to a few raster graphic
       formats: typically `image/gif', `image/jpeg'. In
       particular, `text/html' resources are not
       intended to be used as image resources.
    
    Examples of use:
    
    &lt;IMG SRC="triangle.xbm" ALT="Warning:"&gt; Be sure
    to read these instructions.
    
    &lt;a href="http://machine/htbin/imagemap/sample"&gt;
    &lt;IMG SRC="sample.xbm" ISMAP&gt;
    &lt;/a&gt;
    
    6. Characters, Words, and Paragraphs
    
     An HTML user agent should present the body of an HTML document as a
     collection of typeset paragraphs and preformatted text.  Except for
     preformatted elements (&lt;PRE&gt;, &lt;XMP&gt;, &lt;LISTING&gt;, &lt;TEXTAREA&gt;), each
     block structuring element is regarded as a paragraph by taking the
    
    
    
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     data characters in its content and the content of its descendant
     elements, concatenating them, and splitting the result into words,
     separated by space, tab, or record end characters (and perhaps hyphen
     characters). The sequence of words is typeset as a paragraph by
     breaking it into lines.
    
    6.1. The HTML Document Character Set
    
     The document character set specified in 9.5, "SGML Declaration for
     HTML" must be supported by HTML user agents. It includes the graphic
     characters of Latin Alphabet No. 1, or simply Latin-1.  Latin-1
     comprises 191 graphic characters, including the alphabets of most
     Western European languages.
    
      NOTE - Use of the non-breaking space and soft hyphen indicator
      characters is discouraged because support for them is not widely
      deployed.
    
      NOTE - To support non-western writing systems, a larger character
      repertoire will be specified in a future version of HTML. The
      document character set will be [ISO-10646], or some subset that
      agrees with [ISO-10646]; in particular, all numeric character
      references must use code positions assigned by [ISO-10646].
    
     In SGML applications, the use of control characters is limited in
     order to maximize the chance of successful interchange over
     heterogeneous networks and operating systems. In the HTML document
     character set only three control characters are allowed: Horizontal
     Tab, Carriage Return, and Line Feed (code positions 9, 13, and 10).
    
     The HTML DTD references the Added Latin 1 entity set, to allow
     mnemonic representation of selected Latin 1 characters using only the
     widely supported ASCII character repertoire. For example:
    
     Kurt Gödel was a famous logician and mathematician.
    
     See 9.7.2, "ISO Latin 1 Character Entity Set" for a table of the
     "Added Latin 1" entities, and 13, "The HTML Coded Character Set" for
     a table of the code positions of [ISO 8859-1] and the control
     characters in the HTML document character set.
    
    7. Hyperlinks
    
     In addition to general purpose elements such as paragraphs and lists,
     HTML documents can express hyperlinks. An HTML user agent allows the
     user to navigate these hyperlinks.
    
    
    
    
    
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     A hyperlink is a relationship between two anchors, called the head
     and the tail of the hyperlink[DEXTER]. Anchors are identified by an
     anchor address: an absolute Uniform Resource Identifier (URI),
     optionally followed by a '#' and a sequence of characters called a
     fragment identifier. For example:
    
     http://www.w3.org/hypertext/WWW/TheProject.html
     http://www.w3.org/hypertext/WWW/TheProject.html#z31
    
     In an anchor address, the URI refers to a resource; it may be used in
     a variety of information retrieval protocols to obtain an entity that
     represents the resource, such as an HTML document. The fragment
     identifier, if present, refers to some view on, or portion of the
     resource.
    
     Each of the following markup constructs indicates the tail anchor of
     a hyperlink or set of hyperlinks:
    
      * &lt;A&gt; elements with HREF present.
    
      * &lt;LINK&gt; elements.
    
      * &lt;IMG&gt; elements.
    
      * &lt;INPUT&gt; elements with the SRC attribute present.
    
      * &lt;ISINDEX&gt; elements.
    
      * &lt;FORM&gt; elements with `METHOD=GET'.
    
     These markup constructs refer to head anchors by a URI, either
     absolute or relative, or a fragment identifier, or both.
    
     In the case of a relative URI, the absolute URI in the address of the
     head anchor is the result of combining the relative URI with a base
     absolute URI as in [RELURL]. The base document is taken from the
     document's &lt;BASE&gt; element, if present; else, it is determined as in
     [RELURL].
    
    7.1. Accessing Resources
    
     Once the address of the head anchor is determined, the user agent may
     obtain a representation of the resource.
    
     For example, if the base URI is `http://host/x/y.html' and the
     document contains:
    
     &lt;img src="../icons/abc.gif"&gt;
    
    
    
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     then the user agent uses the URI `http://host/icons/abc.gif' to
     access the resource, as in [URL]..
    
    7.2. Activation of Hyperlinks
    
     An HTML user agent allows the user to navigate the content of the
     document and request activation of hyperlinks denoted by &lt;A&gt;
     elements. HTML user agents should also allow activation of &lt;LINK&gt;
     element hyperlinks.
    
     To activate a link, the user agent obtains a representation of the
     resource identified in the address of the head anchor. If the
     representation is another HTML document, navigation may begin again
     with this new document.
    
    7.3. Simultaneous Presentation of Image Resources
    
     An HTML user agent may activate hyperlinks indicated by &lt;IMG&gt; and
     &lt;INPUT&gt; elements concurrently with processing the document; that is,
     image hyperlinks may be processed without explicit request by the
     user. Image resources should be embedded in the presentation at the
     point of the tail anchor, that is the &lt;IMG&gt; or &lt;INPUT&gt; element.
    
     &lt;LINK&gt; hyperlinks may also be processed without explicit user
     request; for example, style sheet resources may be processed before
     or during the processing of the document.
    
    7.4. Fragment Identifiers
    
     Any characters following a `#' character in a hypertext address
     constitute a fragment identifier. In particular, an address of the
     form `#fragment' refers to an anchor in the same document.
    
     The meaning of fragment identifiers depends on the media type of the
     representation of the anchor's resource. For `text/html'
     representations, it refers to the &lt;A&gt; element with a NAME attribute
     whose value is the same as the fragment identifier.  The matching is
     case sensitive. The document should have exactly one such element.
     The user agent should indicate the anchor element, for example by
     scrolling to and/or highlighting the phrase.
    
     For example, if the base URI is `http://host/x/y.html' and the user
     activated the link denoted by the following markup:
    
     &lt;p&gt; See: &lt;a href="app1.html#bananas"&gt;appendix 1&lt;/a&gt;
     for more detail on bananas.
    
    
    
    
    
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     Then the user agent accesses the resource identified by
     `http://host/x/app1.html'. Assuming the resource is represented using
     the `text/html' media type, the user agent must locate the &lt;A&gt;
     element whose NAME attribute is `bananas' and begin navigation there.
    
    7.5. Queries and Indexes
    
     The &lt;ISINDEX&gt; element represents a set of hyperlinks. The user can
     choose from the set by providing keywords to the user agent.  The
     user agent computes the head URI by appending `?' and the keywords to
     the base URI. The keywords are escaped according to [URL] and joined
     by `+'. For example, if a document contains:
    
    &lt;BASE HREF="http://host/index"&gt;
    &lt;ISINDEX&gt;
    
    and the user provides the keywords `apple' and `berry', then the
    user agent must access the resource
    `http://host/index?apple+berry'.
    
    &lt;FORM&gt; elements with `METHOD=GET' also represent sets of
    hyperlinks. See 8.2.2, "Query Forms: METHOD=GET" for details.
    
    7.6. Image Maps
    
     If the ISMAP attribute is present on an &lt;IMG&gt; element, the &lt;IMG&gt;
     element must be contained in an &lt;A&gt; element with an HREF present.
     This construct represents a set of hyperlinks. The user can choose
     from the set by choosing a pixel of the image. The user agent
     computes the head URI by appending `?' and the x and y coordinates of
     the pixel to the URI given in the &lt;A&gt; element.  For example, if a
     document contains:
    
     &lt;!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN"&gt;
     &lt;head&gt;&lt;title&gt;ImageMap Example
    <p>
       Choose any of these icons:
      <br/>
      <a href="/cgi-bin/imagemap">
        <img ismap="" src="icons.gif"/>
      </a>
      
        and the user chooses the upper-leftmost pixel, the chosen
        hyperlink is the one with the URI
        `http://host/cgi-bin/imagemap?0,0'.
      
      
      
      
      
      
      
      
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      8. Forms
      
        A form is a template for a form data set and an associated
        method and action URI. A form data set is a sequence of
        name/value pair fields. The names are specified on the NAME
        attributes of form input elements, and the values are given
        initial values by various forms of markup and edited by the
        user. The resulting form data set is used to access an
        information service as a function of the action and method.
      
        Forms elements can be mixed in with document structuring
        elements. For example, a 
    </p>
    <PRE> element may contain a </PRE>
    <FORM>
     element, or a </FORM>
    <FORM>
       element may contain lists which contain
      <INPUT/>
       elements. This gives considerable flexibility in
        designing the layout of forms.
      
        Form processing is a level 2 feature.
      
      8.1. Form Elements
      
      8.1.1. Form: FORM
      
        The 
      
      
      
      
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        The initial state of the form data set is:
      
        name
         ""
      
        gender
         "male"
      
        family
         ""
      
        other
         ""
      
        nickname
         ""
      
        Note that the radio input has an initial value, while the
        checkbox has none.
      
        The user might edit the fields and request that the form be
        submitted. At that point, suppose the values are:
      
        name
         "John Doe"
      
        gender
         "male"
      
        family
         "5"
      
        city
         "kent"
      
        city
         "miami"
      
        other
         "abc\ndefk"
      
        nickname
         "J&amp;D"
      
        The user agent then conducts an HTTP POST transaction using the URI
        `http://www.w3.org/sample'. The message body would be (ignore the
        line break):
      
      
      
      
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        name=John+Doe&amp;gender=male&amp;family=5&amp;city=kent&amp;city=miami&amp;
      
        other=abc%0D%0Adef&amp;nickname=J%26D
      
      9. HTML Public Text
      
      9.1. HTML DTD
      
        This is the Document Type Definition for the HyperText Markup
        Language, level 2.
      
      &lt;!--    html.dtd
      
        Document Type Definition for the HyperText Markup Language
            (HTML DTD)
      
        $Id: html.dtd,v 1.30 1995/09/21 23:30:19 connolly Exp $
      
        Author: Daniel W. Connolly 
      <H1>
        <a name="xxx">Heading</a>
      </H1>
      <connolly w3.org="">
        See Also: html.decl, html-1.dtd
          http://www.w3.org/hypertext/WWW/MarkUp/MarkUp.html
        --&gt;
        
        &lt;!ENTITY % HTML.Version
        "-//IETF//DTD HTML 2.0//EN"
        
        -- Typical usage:
        
            &lt;!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML//EN"&gt;
            ...
        --
        &gt;
        
        
        &lt;!--============ Feature Test Entities ========================--&gt;
        
        &lt;!ENTITY % HTML.Recommended "IGNORE"
        -- Certain features of the language are necessary for
           compatibility with widespread usage, but they may
           compromise the structural integrity of a document.
           This feature test entity enables a more prescriptive
           document type definition that eliminates
           those features.
        --&gt;
        
        &lt;![ %HTML.Recommended [
        &lt;!ENTITY % HTML.Deprecated "IGNORE"&gt;
        
        
        
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        ]]&gt;
        
        &lt;!ENTITY % HTML.Deprecated "INCLUDE"
        -- Certain features of the language are necessary for
           compatibility with earlier versions of the specification,
           but they tend to be used and implemented inconsistently,
           and their use is deprecated. This feature test entity
           enables a document type definition that eliminates
           these features.
        --&gt;
        
        &lt;!ENTITY % HTML.Highlighting "INCLUDE"
        -- Use this feature test entity to validate that a
           document uses no highlighting tags, which may be
           ignored on minimal implementations.
        --&gt;
        
        &lt;!ENTITY % HTML.Forms "INCLUDE"
        -- Use this feature test entity to validate that a document
           contains no forms, which may not be supported in minimal
           implementations
        --&gt;
        
        &lt;!--============== Imported Names ==============================--&gt;
        
        &lt;!ENTITY % Content-Type "CDATA"
        -- meaning an internet media type
           (aka MIME content type, as per RFC1521)
        --&gt;
        
        &lt;!ENTITY % HTTP-Method "GET | POST"
        -- as per HTTP specification, in progress
        --&gt;
        
        &lt;!--========= DTD "Macros" =====================--&gt;
        
        &lt;!ENTITY % heading "H1|H2|H3|H4|H5|H6"&gt;
        
        &lt;!ENTITY % list " UL | OL | DIR | MENU " &gt;
        
        
        &lt;!--======= Character mnemonic entities =================--&gt;
        
        &lt;!ENTITY % ISOlat1 PUBLIC
          "ISO 8879-1986//ENTITIES Added Latin 1//EN//HTML"&gt;
        %ISOlat1;
        
        &lt;!ENTITY amp CDATA "&amp;"     -- ampersand          --&gt;
        
        
        
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        &lt;!ENTITY gt CDATA "&gt;"      -- greater than       --&gt;
        &lt;!ENTITY lt CDATA "&lt;"      -- less than          --&gt;
        &lt;!ENTITY quot CDATA """    -- double quote       --&gt;
        
        
        &lt;!--========= SGML Document Access (SDA) Parameter Entities =====--&gt;
        
        &lt;!-- HTML 2.0 contains SGML Document Access (SDA) fixed attributes
        in support of easy transformation to the International Committee
        for Accessible Document Design (ICADD) DTD
         "-//EC-USA-CDA/ICADD//DTD ICADD22//EN".
        ICADD applications are designed to support usable access to
        structured information by print-impaired individuals through
        Braille, large print and voice synthesis.  For more information on
        SDA &amp;  ICADD:
        - ISO 12083:1993, Annex A.8, Facilities for Braille,
          large print and computer voice
        - ICADD ListServ
        <ICADD ASUACAD.BITNET="" ARIZVM1.ccit.arizona.edu="">
            - Usenet news group bit.listserv.easi
            - Recording for the Blind, +1 800 221 4792
          --&gt;
          
          &lt;!ENTITY % SDAFORM  "SDAFORM  CDATA  #FIXED"
          -- one to one mapping        --&gt;
          &lt;!ENTITY % SDARULE  "SDARULE  CDATA  #FIXED"
          -- context-sensitive mapping --&gt;
          &lt;!ENTITY % SDAPREF  "SDAPREF  CDATA  #FIXED"
          -- generated text prefix     --&gt;
          &lt;!ENTITY % SDASUFF  "SDASUFF  CDATA  #FIXED"
          -- generated text suffix     --&gt;
          &lt;!ENTITY % SDASUSP  "SDASUSP  NAME   #FIXED"
          -- suspend transform process --&gt;
          
          
          &lt;!--========== Text Markup =====================--&gt;
          
          &lt;![ %HTML.Highlighting [
          
          &lt;!ENTITY % font " TT | B | I "&gt;
          
          &lt;!ENTITY % phrase "EM | STRONG | CODE | SAMP | KBD | VAR | CITE "&gt;
          
          &lt;!ENTITY % text "#PCDATA | A | IMG | BR | %phrase | %font"&gt;
          
          &lt;!ELEMENT (%font;|%phrase) - - (%text)*&gt;
          &lt;!ATTLIST ( TT | CODE | SAMP | KBD | VAR )
            %SDAFORM; "Lit"
          
          
          
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            &gt;
          &lt;!ATTLIST ( B | STRONG )
            %SDAFORM; "B"
            &gt;
          &lt;!ATTLIST ( I | EM | CITE )
            %SDAFORM; "It"
            &gt;
          
          &lt;!-- 
          <TT>
                   Typewriter text                         --&gt;
            &lt;!-- 
            <B>
                      Bold text                               --&gt;
              &lt;!-- 
              <I>
                        Italic text                             --&gt;
                
                &lt;!-- 
                <EM>
                         Emphasized phrase                       --&gt;
                  &lt;!-- 
                  <STRONG>
                       Strong emphasis                         --&gt;
                    &lt;!-- 
                    <CODE>
                           Source code phrase                      --&gt;
                      &lt;!-- 
                      <SAMP>
                             Sample text or characters               --&gt;
                        &lt;!-- 
                        <KBD>
                                Keyboard phrase, e.g. user input        --&gt;
                          &lt;!-- 
                          <VAR>
                                  Variable phrase or substitutable        --&gt;
                            &lt;!-- 
                            <CITE>
                                   Name or title of cited work             --&gt;
                              
                              &lt;!ENTITY % pre.content "#PCDATA | A | HR | BR | %font | %phrase"&gt;
                              
                              ]]&gt;
                              
                              &lt;!ENTITY % text "#PCDATA | A | IMG | BR"&gt;
                              
                              &lt;!ELEMENT BR    - O EMPTY&gt;
                              &lt;!ATTLIST BR
                                     %SDAPREF; "RE;"
                                     &gt;
                              
                              &lt;!-- 
                              <BR/>
                                     Line break      --&gt;
                              
                              
                              &lt;!--========= Link Markup ======================--&gt;
                              
                              &lt;!ENTITY % linkType "NAMES"&gt;
                              
                              &lt;!ENTITY % linkExtraAttributes
                                     "REL %linkType #IMPLIED
                                     REV %linkType #IMPLIED
                                     URN CDATA #IMPLIED
                                     TITLE CDATA #IMPLIED
                                     METHODS NAMES #IMPLIED
                                     "&gt;
                              
                              &lt;![ %HTML.Recommended [
                                     &lt;!ENTITY % A.content   "(%text)*"
                              
                              
                              
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                                     -- 
                                            is preferred to
                              <a name="xxx"></a>
                                     --&gt;
                              ]]&gt;
                              
                              &lt;!ENTITY % A.content   "(%heading|%text)*"&gt;
                              
                              &lt;!ELEMENT A     - - %A.content -(A)&gt;
                              &lt;!ATTLIST A
                                     HREF CDATA #IMPLIED
                                     NAME CDATA #IMPLIED
                                     %linkExtraAttributes;
                                     %SDAPREF; "
                              <Anchor:AttList>
                                "
                                      &gt;
                                &lt;!-- 
                                <A>                Anchor; source/destination of link      --&gt;
                                &lt;!-- </A>
                              </Anchor:AttList>
                              <A NAME="...">     Name of this anchor                     --&gt;
                              &lt;!-- </A>
                              <A HREF="...">     Address of link destination             --&gt;
                              &lt;!-- </A>
                              <A URN="...">      Permanent address of destination        --&gt;
                              &lt;!-- </A>
                              <A REL="...">        Relationship to destination             --&gt;
                              &lt;!-- </A>
                              <A REV="...">        Relationship of destination to this     --&gt;
                              &lt;!-- </A>
                              <A TITLE="...">    Title of destination (advisory)         --&gt;
                              &lt;!-- </A>
                              <A METHODS="...">
                                  Operations on destination (advisory)    --&gt;
                                
                                
                                &lt;!--========== Images ==========================--&gt;
                                
                                &lt;!ELEMENT IMG    - O EMPTY&gt;
                                &lt;!ATTLIST IMG
                                      SRC CDATA  #REQUIRED
                                      ALT CDATA #IMPLIED
                                      ALIGN (top|middle|bottom) #IMPLIED
                                      ISMAP (ISMAP) #IMPLIED
                                      %SDAPREF; "
                                <Fig>
                                  <?SDATrans Img: #AttList?>
                                  #AttVal(Alt)
                                </Fig>
                                "
                                      &gt;
                                
                                &lt;!-- 
                                <IMG/>
                                              Image; icon, glyph or illustration      --&gt;
                                &lt;!-- 
                                <IMG SRC="..."/>
                                    Address of image object                 --&gt;
                                &lt;!-- 
                                <IMG ALT="..."/>
                                    Textual alternative                     --&gt;
                                &lt;!-- 
                                <IMG ALIGN="..."/>
                                    Position relative to text               --&gt;
                                &lt;!-- 
                                <IMG ISMAP=""/>
                                        Each pixel can be a link                --&gt;
                                
                                &lt;!--========== Paragraphs=======================--&gt;
                                
                                &lt;!ELEMENT P     - O (%text)*&gt;
                                &lt;!ATTLIST P
                                      %SDAFORM; "Para"
                                      &gt;
                                
                                
                                
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                                RFC 1866            Hypertext Markup Language - 2.0        November 1995
                                
                                
                                &lt;!-- 
                              </A>
                            </CITE>
                          </VAR>
                        </KBD>
                      </SAMP>
                    </CODE>
                  </STRONG>
                </EM>
              </I>
            </B>
          </TT>
        </ICADD>
      </connolly>
      <P>
                Paragraph       --&gt;
        
        
        &lt;!--========== Headings, Titles, Sections ===============--&gt;
        
        &lt;!ELEMENT HR    - O EMPTY&gt;
        &lt;!ATTLIST HR
        %SDAPREF; "RE;RE;"
        &gt;
        
        &lt;!-- 
               Horizontal rule --&gt;
        
        &lt;!ELEMENT ( %heading )  - -  (%text;)*&gt;
        &lt;!ATTLIST H1
        %SDAFORM; "H1"
        &gt;
        &lt;!ATTLIST H2
        %SDAFORM; "H2"
        &gt;
        &lt;!ATTLIST H3
        %SDAFORM; "H3"
        &gt;
        &lt;!ATTLIST H4
        %SDAFORM; "H4"
        &gt;
        &lt;!ATTLIST H5
        %SDAFORM; "H5"
        &gt;
        &lt;!ATTLIST H6
        %SDAFORM; "H6"
        &gt;
        
        &lt;!-- 
      </P>
      <HR/>
      <H1>       Heading, level 1 --&gt;
      &lt;!-- </H1>
      <H2>       Heading, level 2 --&gt;
      &lt;!-- </H2>
      <H3>       Heading, level 3 --&gt;
      &lt;!-- </H3>
      <H4>       Heading, level 4 --&gt;
      &lt;!-- </H4>
      <H5>       Heading, level 5 --&gt;
      &lt;!-- </H5>
      <H6>       Heading, level 6 --&gt;
      
      
      &lt;!--========== Text Flows ======================--&gt;
      
      &lt;![ %HTML.Forms [
        &lt;!ENTITY % block.forms "BLOCKQUOTE | FORM | ISINDEX"&gt;
      ]]&gt;
      
      &lt;!ENTITY % block.forms "BLOCKQUOTE"&gt;
      
      
      
      
      Berners-Lee &amp;  Connolly      Standards Track                    [Page 54]
      
      RFC 1866            Hypertext Markup Language - 2.0        November 1995
      
      
      &lt;![ %HTML.Deprecated [
        &lt;!ENTITY % preformatted "PRE | XMP | LISTING"&gt;
      ]]&gt;
      
      &lt;!ENTITY % preformatted "PRE"&gt;
      
      &lt;!ENTITY % block "P | %list | DL
        | %preformatted
        | %block.forms"&gt;
      
      &lt;!ENTITY % flow "(%text|%block)*"&gt;
      
      &lt;!ENTITY % pre.content "#PCDATA | A | HR | BR"&gt;
      &lt;!ELEMENT PRE - - (%pre.content)*&gt;
      &lt;!ATTLIST PRE
        WIDTH NUMBER #implied
        %SDAFORM; "Lit"
        &gt;
      
      &lt;!-- </H6>
      <PRE>              Preformatted text               --&gt;
      &lt;!-- </PRE>
      <PRE WIDTH="...">
            Maximum characters per line     --&gt;
        
        &lt;![ %HTML.Deprecated [
        
        &lt;!ENTITY % literal "CDATA"
        -- historical, non-conforming parsing mode where
           the only markup signal is the end tag
           in full
        --&gt;
        
        &lt;!ELEMENT (XMP|LISTING) - -  %literal&gt;
        &lt;!ATTLIST XMP
        %SDAFORM; "Lit"
        %SDAPREF; "Example:RE;"
        &gt;
        &lt;!ATTLIST LISTING
        %SDAFORM; "Lit"
        %SDAPREF; "Listing:RE;"
        &gt;
        
        &lt;!-- 
        <XMP>
                        Example section         --&gt;
          &lt;!-- 
          <LISTING>
                      Computer listing        --&gt;
            
            &lt;!ELEMENT PLAINTEXT - O %literal&gt;
            &lt;!-- 
            <PLAINTEXT>
                      Plain text passage      --&gt;
              
              &lt;!ATTLIST PLAINTEXT
                    %SDAFORM; "Lit"
              
              
              
              Berners-Lee &amp;  Connolly      Standards Track                    [Page 55]
              
              RFC 1866            Hypertext Markup Language - 2.0        November 1995
              
              
                    &gt;
              ]]&gt;
              
              &lt;!--========== Lists ==================--&gt;
              
              &lt;!ELEMENT DL    - -  (DT | DD)+&gt;
              &lt;!ATTLIST DL
                    COMPACT (COMPACT) #IMPLIED
                    %SDAFORM; "List"
                    %SDAPREF; "Definition List:"
                    &gt;
              
              &lt;!ELEMENT DT    - O (%text)*&gt;
              &lt;!ATTLIST DT
                    %SDAFORM; "Term"
                    &gt;
              
              &lt;!ELEMENT DD    - O %flow&gt;
              &lt;!ATTLIST DD
                    %SDAFORM; "LItem"
                    &gt;
              
              &lt;!-- 
              <DL>
                <DT>               Definition list, or glossary    --&gt;
                &lt;!-- </DT>
              </DL>
            </PLAINTEXT>
          </LISTING>
        </XMP>
      </PRE>
      <DL COMPACT="">
        <DT>
                 Compact style list              --&gt;
          &lt;!-- 
                         Term in definition list         --&gt;
          &lt;!-- 
        </DT>
        <DD>
                         Definition of term              --&gt;
          
          &lt;!ELEMENT (OL|UL) - -  (LI)+&gt;
          &lt;!ATTLIST OL
            COMPACT (COMPACT) #IMPLIED
            %SDAFORM; "List"
            &gt;
          &lt;!ATTLIST UL
            COMPACT (COMPACT) #IMPLIED
            %SDAFORM; "List"
            &gt;
          &lt;!-- 
          <UL>
                           Unordered list                  --&gt;
            &lt;!-- 
            <UL COMPACT="">
                     Compact list style              --&gt;
              &lt;!-- 
              <OL>
                               Ordered, or numbered list       --&gt;
                &lt;!-- 
                <OL COMPACT="">
                         Compact list style              --&gt;
                  
                  
                  &lt;!ELEMENT (DIR|MENU) - -  (LI)+ -(%block)&gt;
                  &lt;!ATTLIST DIR
                       COMPACT (COMPACT) #IMPLIED
                       %SDAFORM; "List"
                       %SDAPREF; "
                  <LHead>Directory</LHead>
                  "
                       &gt;
                  
                  
                  
                  Berners-Lee &amp;  Connolly      Standards Track                    [Page 56]
                  
                  RFC 1866            Hypertext Markup Language - 2.0        November 1995
                  
                  
                  &lt;!ATTLIST MENU
                       COMPACT (COMPACT) #IMPLIED
                       %SDAFORM; "List"
                       %SDAPREF; "
                  <LHead>Menu</LHead>
                  "
                       &gt;
                  
                  &lt;!-- 
                  <DIR>
                    <LI>
                                    Directory list                  --&gt;
                      &lt;!-- 
                      <DIR COMPACT="">
                        <LI>
                                Compact list style              --&gt;
                          &lt;!-- 
                          <MENU>
                            <LI>
                                           Menu list                       --&gt;
                              &lt;!-- 
                              <MENU COMPACT="">
                                <LI>
                                       Compact list style              --&gt;
                                  
                                  &lt;!ELEMENT LI    - O %flow&gt;
                                  &lt;!ATTLIST LI
                                        %SDAFORM; "LItem"
                                        &gt;
                                  
                                  &lt;!-- 
                                                 List item                       --&gt;
                                  
                                  &lt;!--========== Document Body ===================--&gt;
                                  
                                  &lt;![ %HTML.Recommended [
                                        &lt;!ENTITY % body.content "(%heading|%block|HR|ADDRESS|IMG)*"
                                        -- 
                                  <h1>Heading</h1>
                                  <p>Text ...
                                           is preferred to</p>
                                  <h1>Heading</h1>
                                          Text ...
                                        --&gt;
                                  ]]&gt;
                                  
                                  &lt;!ENTITY % body.content "(%heading | %text | %block |
                                   HR | ADDRESS)*"&gt;
                                  
                                  &lt;!ELEMENT BODY O O  %body.content&gt;
                                  
                                  &lt;!-- 
                                       Document body   --&gt;
                                  
                                  &lt;!ELEMENT BLOCKQUOTE - - %body.content&gt;
                                  &lt;!ATTLIST BLOCKQUOTE
                                        %SDAFORM; "BQ"
                                        &gt;
                                  
                                  &lt;!-- 
                                  <BLOCKQUOTE>
                                           Quoted passage  --&gt;
                                    
                                    &lt;!ELEMENT ADDRESS - - (%text|P)*&gt;
                                    &lt;!ATTLIST  ADDRESS
                                           %SDAFORM; "Lit"
                                           %SDAPREF; "Address:RE;"
                                    
                                    
                                    
                                    Berners-Lee &amp;  Connolly      Standards Track                    [Page 57]
                                    
                                    RFC 1866            Hypertext Markup Language - 2.0        November 1995
                                    
                                    
                                           &gt;
                                    
                                    &lt;!-- 
                                    <ADDRESS>
                                        Address, signature, or byline   --&gt;
                                      
                                      
                                      &lt;!--======= Forms ====================--&gt;
                                      
                                      &lt;![ %HTML.Forms [
                                      
                                      &lt;!ELEMENT FORM - - %body.content -(FORM) +(INPUT|SELECT|TEXTAREA)&gt;
                                      &lt;!ATTLIST FORM
                                              ACTION CDATA #IMPLIED
                                              METHOD (%HTTP-Method) GET
                                              ENCTYPE %Content-Type; "application/x-www-form-urlencoded"
                                              %SDAPREF; "
                                      <Para>Form:</Para>
                                      "
                                              %SDASUFF; "
                                      <Para>Form End.</Para>
                                      "
                                              &gt;
                                      
                                      &lt;!-- 
                                    </ADDRESS>
                                    <FORM>                     Fill-out or data-entry form     --&gt;
                                    &lt;!-- </FORM>
                                    <FORM ACTION="...">        Address for completed form      --&gt;
                                    &lt;!-- </FORM>
                                    <FORM METHOD="...">          Method of submitting form       --&gt;
                                    &lt;!-- </FORM>
                                    <FORM ENCTYPE="...">
                                             Representation of form data     --&gt;
                                      
                                      &lt;!ENTITY % InputType "(TEXT | PASSWORD | CHECKBOX |
                                                    RADIO | SUBMIT | RESET |
                                                    IMAGE | HIDDEN )"&gt;
                                      &lt;!ELEMENT INPUT - O EMPTY&gt;
                                      &lt;!ATTLIST INPUT
                                              TYPE %InputType TEXT
                                              NAME CDATA #IMPLIED
                                              VALUE CDATA #IMPLIED
                                              SRC CDATA #IMPLIED
                                              CHECKED (CHECKED) #IMPLIED
                                              SIZE CDATA #IMPLIED
                                              MAXLENGTH NUMBER #IMPLIED
                                              ALIGN (top|middle|bottom) #IMPLIED
                                              %SDAPREF; "Input: "
                                              &gt;
                                      
                                      &lt;!-- 
                                      <INPUT/>
                                                          Form input datum                --&gt;
                                      &lt;!-- 
                                      <INPUT TYPE="..."/>
                                                 Type of input interaction       --&gt;
                                      &lt;!-- 
                                      <INPUT NAME="..."/>
                                                 Name of form datum              --&gt;
                                      &lt;!-- 
                                      <INPUT VALUE="..."/>
                                              Default/initial/selected value  --&gt;
                                      &lt;!-- 
                                      <INPUT SRC="..."/>
                                                Address of image                --&gt;
                                      &lt;!-- 
                                      <INPUT CHECKED=""/>
                                                  Initial state is "on"           --&gt;
                                      &lt;!-- 
                                      <INPUT SIZE="..."/>
                                                 Field size hint                 --&gt;
                                      &lt;!-- 
                                      <INPUT MAXLENGTH="..."/>
                                            Data length maximum             --&gt;
                                      &lt;!-- 
                                      <INPUT ALIGN="..."/>
                                                Image alignment                 --&gt;
                                      
                                      
                                      
                                      Berners-Lee &amp;  Connolly      Standards Track                    [Page 58]
                                      
                                      RFC 1866            Hypertext Markup Language - 2.0        November 1995
                                      
                                      
                                      &lt;!ELEMENT SELECT - - (OPTION+) -(INPUT|SELECT|TEXTAREA)&gt;
                                      &lt;!ATTLIST SELECT
                                              NAME CDATA #REQUIRED
                                              SIZE NUMBER #IMPLIED
                                              MULTIPLE (MULTIPLE) #IMPLIED
                                              %SDAFORM; "List"
                                              %SDAPREF;
                                              "
                                      <LHead>Select #AttVal(Multiple)</LHead>
                                      "
                                              &gt;
                                      
                                      &lt;!-- 
                                                Multiple selections allowed     --&gt;
                                      
                                      &lt;!ELEMENT OPTION - O (#PCDATA)*&gt;
                                      &lt;!ATTLIST OPTION
                                              SELECTED (SELECTED) #IMPLIED
                                              VALUE CDATA #IMPLIED
                                              %SDAFORM; "LItem"
                                              %SDAPREF;
                                              "Option: #AttVal(Value) #AttVal(Selected)"
                                              &gt;
                                      
                                      &lt;!-- 
                                      <SELECT>
                                        <OPTGROUP>
                                          <OPTION>Undefined</OPTION>
                                        </OPTGROUP>
                                      </SELECT>
                                                         Selection of option(s)          --&gt;
                                      &lt;!-- 
                                      <SELECT NAME="...">
                                        <OPTGROUP>
                                          <OPTION>Undefined</OPTION>
                                        </OPTGROUP>
                                      </SELECT>
                                                Name of form datum              --&gt;
                                      &lt;!-- 
                                      <SELECT SIZE="...">
                                        <OPTGROUP>
                                          <OPTION>Undefined</OPTION>
                                        </OPTGROUP>
                                      </SELECT>
                                                Options displayed at a time     --&gt;
                                      &lt;!-- 
                                      <SELECT MULTIPLE="">
                                        <OPTION>                   A selection option              --&gt;
                                        &lt;!-- &lt;OPTION SELECTED&gt;          Initial state                   --&gt;
                                        &lt;!-- &lt;OPTION VALUE="..."&gt;       Form datum value for this option--&gt;
                                        
                                        &lt;!ELEMENT TEXTAREA - - (#PCDATA)* -(INPUT|SELECT|TEXTAREA)&gt;
                                        &lt;!ATTLIST TEXTAREA
                                              NAME CDATA #REQUIRED
                                              ROWS NUMBER #REQUIRED
                                              COLS NUMBER #REQUIRED
                                              %SDAFORM; "Para"
                                              %SDAPREF; "Input Text -- #AttVal(Name): "
                                              &gt;
                                        
                                        &lt;!-- &lt;TEXTAREA&gt;                 An area for text input          --&gt;
                                        &lt;!-- &lt;TEXTAREA NAME=...&gt;        Name of form datum              --&gt;
                                        &lt;!-- &lt;TEXTAREA ROWS=...&gt;        Height of area                  --&gt;
                                        &lt;!-- &lt;TEXTAREA COLS=...&gt;        Width of area                   --&gt;
                                        
                                        ]]&gt;
                                        
                                        
                                        &lt;!--======= Document Head ======================--&gt;
                                        
                                        &lt;![ %HTML.Recommended [
                                        
                                        
                                        
                                        Berners-Lee &amp;  Connolly      Standards Track                    [Page 59]
                                        
                                        RFC 1866            Hypertext Markup Language - 2.0        November 1995
                                        
                                        
                                              &lt;!ENTITY % head.extra ""&gt;
                                        ]]&gt;
                                        &lt;!ENTITY % head.extra "&amp;  NEXTID?"&gt;
                                        
                                        &lt;!ENTITY % head.content "TITLE &amp;  ISINDEX? &amp;  BASE? %head.extra"&gt;
                                        
                                        &lt;!ELEMENT HEAD O O  (%head.content) +(META|LINK)&gt;
                                        
                                        &lt;!-- &lt;HEAD&gt;     Document head   --&gt;
                                        
                                        &lt;!ELEMENT TITLE - -  (#PCDATA)*  -(META|LINK)&gt;
                                        &lt;!ATTLIST TITLE
                                              %SDAFORM; "Ti"    &gt;
                                        
                                        &lt;!-- &lt;TITLE&gt;    Title of document --&gt;
                                        
                                        &lt;!ELEMENT LINK - O EMPTY&gt;
                                        &lt;!ATTLIST LINK
                                              HREF CDATA #REQUIRED
                                              %linkExtraAttributes;
                                              %SDAPREF; "Linked to : #AttVal (TITLE) (URN) (HREF)&gt;"    &gt;
                                        
                                        &lt;!-- &lt;LINK&gt;             Link from this document                 --&gt;
                                        &lt;!-- &lt;LINK HREF="..."&gt;  Address of link destination             --&gt;
                                        &lt;!-- &lt;LINK URN="..."&gt;   Lasting name of destination             --&gt;
                                        &lt;!-- &lt;LINK REL=...&gt;     Relationship to destination             --&gt;
                                        &lt;!-- &lt;LINK REV=...&gt;     Relationship of destination to this     --&gt;
                                        &lt;!-- &lt;LINK TITLE="..."&gt; Title of destination (advisory)         --&gt;
                                        &lt;!-- &lt;LINK METHODS="..."&gt; Operations allowed (advisory)         --&gt;
                                        
                                        &lt;!ELEMENT ISINDEX - O EMPTY&gt;
                                        &lt;!ATTLIST ISINDEX
                                              %SDAPREF;
                                           "&lt;Para&gt;[Document is indexed/searchable.]&lt;/Para&gt;"&gt;
                                        
                                        &lt;!-- &lt;ISINDEX&gt;          Document is a searchable index          --&gt;
                                        
                                        &lt;!ELEMENT BASE - O EMPTY&gt;
                                        &lt;!ATTLIST BASE
                                              HREF CDATA #REQUIRED     &gt;
                                        
                                        &lt;!-- &lt;BASE&gt;             Base context document                   --&gt;
                                        &lt;!-- &lt;BASE HREF="..."&gt;  Address for this document               --&gt;
                                        
                                        &lt;!ELEMENT NEXTID - O EMPTY&gt;
                                        &lt;!ATTLIST NEXTID
                                              N CDATA #REQUIRED     &gt;
                                        
                                        
                                        
                                        
                                        Berners-Lee &amp;  Connolly      Standards Track                    [Page 60]
                                        
                                        RFC 1866            Hypertext Markup Language - 2.0        November 1995
                                        
                                        
                                        &lt;!-- &lt;NEXTID&gt;           Next ID to use for link name            --&gt;
                                        &lt;!-- &lt;NEXTID N=...&gt;     Next ID to use for link name            --&gt;
                                        
                                        &lt;!ELEMENT META - O EMPTY&gt;
                                        &lt;!ATTLIST META
                                              HTTP-EQUIV  NAME    #IMPLIED
                                              NAME        NAME    #IMPLIED
                                              CONTENT     CDATA   #REQUIRED    &gt;
                                        
                                        &lt;!-- &lt;META&gt;                     Generic Meta-information        --&gt;
                                        &lt;!-- &lt;META HTTP-EQUIV=...&gt;      HTTP response header name       --&gt;
                                        &lt;!-- &lt;META NAME=...&gt;            Meta-information name           --&gt;
                                        &lt;!-- &lt;META CONTENT="..."&gt;       Associated information          --&gt;
                                        
                                        &lt;!--======= Document Structure =================--&gt;
                                        
                                        &lt;![ %HTML.Deprecated [
                                              &lt;!ENTITY % html.content "HEAD, BODY, PLAINTEXT?"&gt;
                                        ]]&gt;
                                        &lt;!ENTITY % html.content "HEAD, BODY"&gt;
                                        
                                        &lt;!ELEMENT HTML O O  (%html.content)&gt;
                                        &lt;!ENTITY % version.attr "VERSION CDATA #FIXED '%HTML.Version;'"&gt;
                                        
                                        &lt;!ATTLIST HTML
                                              %version.attr;
                                              %SDAFORM; "Book"
                                              &gt;
                                        
                                        &lt;!-- &lt;HTML&gt;                     HTML Document   --&gt;
                                        
                                        9.2. Strict HTML DTD
                                        
                                           This document type declaration refers to the HTML DTD with the
                                           `HTML.Recommended' entity defined as `INCLUDE' rather than IGNORE;
                                           that is, it refers to the more structurally rigid definition of HTML.
                                        
                                        &lt;!--    html-s.dtd
                                        
                                              Document Type Definition for the HyperText Markup Language
                                              with strict validation (HTML Strict DTD).
                                        
                                              $Id: html-s.dtd,v 1.3 1995/06/02 18:55:46 connolly Exp $
                                        
                                              Author: Daniel W. Connolly &lt;connolly@w3.org&gt;
                                              See Also: http://www.w3.org/hypertext/WWW/MarkUp/MarkUp.html
                                        --&gt;
                                        
                                        
                                        
                                        
                                        Berners-Lee &amp;  Connolly      Standards Track                    [Page 61]
                                        
                                        RFC 1866            Hypertext Markup Language - 2.0        November 1995
                                        
                                        
                                        &lt;!ENTITY % HTML.Version
                                              "-//IETF//DTD HTML 2.0 Strict//EN"
                                        
                                              -- Typical usage:
                                        
                                                 &lt;!DOCTYPE HTML PUBLIC
                                                    "-//IETF//DTD HTML Strict//EN"&gt;
                                                 &lt;html&gt;
                                                 ...
                                                 &lt;/html&gt;
                                              --
                                              &gt;
                                        
                                        &lt;!-- Feature Test Entities --&gt;
                                        &lt;!ENTITY % HTML.Recommended "INCLUDE"&gt;
                                        
                                        &lt;!ENTITY % html PUBLIC "-//IETF//DTD HTML 2.0//EN"&gt;
                                        %html;
                                        
                                        9.3. Level 1 HTML DTD
                                        
                                           This document type declaration refers to the HTML DTD with the
                                           `HTML.Forms' entity defined as `IGNORE' rather than `INCLUDE'.
                                           Documents which contain &lt;FORM&gt; elements do not conform to this DTD,
                                           and must use the level 2 DTD.
                                        
                                        &lt;!--    html-1.dtd
                                        
                                              Document Type Definition for the HyperText Markup Language
                                              with Level 1 Extensions (HTML Level 1 DTD).
                                        
                                              $Id: html-1.dtd,v 1.2 1995/03/29 18:53:10 connolly Exp $
                                        
                                              Author: Daniel W. Connolly &lt;connolly@w3.org&gt;
                                              See Also: http://info.cern.ch/hypertext/WWW/MarkUp/MarkUp.html
                                        
                                        --&gt;
                                        
                                        &lt;!ENTITY % HTML.Version
                                              "-//IETF//DTD HTML 2.0 Level 1//EN"
                                        
                                              -- Typical usage:
                                        
                                                 &lt;!DOCTYPE HTML PUBLIC
                                                    "-//IETF//DTD HTML Level 1//EN"&gt;
                                                 &lt;html&gt;
                                                 ...
                                                 &lt;/html&gt;
                                        
                                        
                                        
                                        Berners-Lee &amp;  Connolly      Standards Track                    [Page 62]
                                        
                                        RFC 1866            Hypertext Markup Language - 2.0        November 1995
                                        
                                        
                                              --
                                              &gt;
                                        
                                        &lt;!-- Feature Test Entities --&gt;
                                        &lt;!ENTITY % HTML.Forms "IGNORE"&gt;
                                        
                                        &lt;!ENTITY % html PUBLIC "-//IETF//DTD HTML 2.0//EN"&gt;
                                        %html;
                                        
                                        9.4. Strict Level 1 HTML DTD
                                        
                                           This document type declaration refers to the level 1 HTML DTD with
                                           the `HTML.Recommended' entity defined as `INCLUDE' rather than
                                           IGNORE; that is, it refers to the more structurally rigid definition
                                           of HTML.
                                        
                                        &lt;!--    html-1s.dtd
                                        
                                              Document Type Definition for the HyperText Markup Language
                                              Struct Level 1
                                        
                                              $Id: html-1s.dtd,v 1.3 1995/06/02 18:55:43 connolly Exp $
                                        
                                              Author: Daniel W. Connolly &lt;connolly@w3.org&gt;
                                              See Also: http://www.w3.org/hypertext/WWW/MarkUp/MarkUp.html
                                        --&gt;
                                        
                                        &lt;!ENTITY % HTML.Version
                                              "-//IETF//DTD HTML 2.0 Strict Level 1//EN"
                                        
                                              -- Typical usage:
                                        
                                                 &lt;!DOCTYPE HTML PUBLIC
                                                    "-//IETF//DTD HTML Strict Level 1//EN"&gt;
                                                 &lt;html&gt;
                                                 ...
                                                 &lt;/html&gt;
                                              --
                                              &gt;
                                        
                                        &lt;!-- Feature Test Entities --&gt;
                                        
                                        
                                        &lt;!ENTITY % HTML.Recommended "INCLUDE"&gt;
                                        
                                        &lt;!ENTITY % html-1 PUBLIC "-//IETF//DTD HTML 2.0 Level 1//EN"&gt;
                                        %html-1;
                                        
                                        
                                        
                                        
                                        Berners-Lee &amp;  Connolly      Standards Track                    [Page 63]
                                        
                                        RFC 1866            Hypertext Markup Language - 2.0        November 1995
                                        
                                        
                                        9.5. SGML Declaration for HTML
                                        
                                           This is the SGML Declaration for HyperText Markup Language.
                                        
                                        &lt;!SGML  "ISO 8879:1986"
                                        --
                                              SGML Declaration for HyperText Markup Language (HTML).
                                        
                                        --
                                        
                                        CHARSET
                                                BASESET  "ISO 646:1983//CHARSET
                                                  International Reference Version
                                                  (IRV)//ESC 2/5 4/0"
                                                DESCSET  0   9   UNUSED
                                                   9   2   9
                                                   11  2   UNUSED
                                                   13  1   13
                                                   14  18  UNUSED
                                                   32  95  32
                                                   127 1   UNUSED
                                            BASESET   "ISO Registration Number 100//CHARSET
                                                    ECMA-94 Right Part of
                                                    Latin Alphabet Nr. 1//ESC 2/13 4/1"
                                        
                                                DESCSET  128  32   UNUSED
                                                   160  96    32
                                        
                                        CAPACITY        SGMLREF
                                                    TOTALCAP        150000
                                                    GRPCAP          150000
                                                    ENTCAP          150000
                                        
                                        SCOPE    DOCUMENT
                                        SYNTAX
                                                SHUNCHAR CONTROLS 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
                                                    17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 127
                                                BASESET  "ISO 646:1983//CHARSET
                                                  International Reference Version
                                                  (IRV)//ESC 2/5 4/0"
                                                DESCSET  0 128 0
                                                FUNCTION
                                                   RE          13
                                                   RS          10
                                                   SPACE       32
                                                   TAB SEPCHAR  9
                                                NAMING   LCNMSTRT ""
                                                   UCNMSTRT ""
                                        
                                        
                                        
                                        Berners-Lee &amp;  Connolly      Standards Track                    [Page 64]
                                        
                                        RFC 1866            Hypertext Markup Language - 2.0        November 1995
                                        
                                        
                                                   LCNMCHAR ".-"
                                                   UCNMCHAR ".-"
                                                   NAMECASE GENERAL YES
                                                     ENTITY  NO
                                                DELIM    GENERAL  SGMLREF
                                                   SHORTREF SGMLREF
                                                NAMES    SGMLREF
                                                QUANTITY SGMLREF
                                                   ATTSPLEN 2100
                                                   LITLEN   1024
                                                   NAMELEN  72    -- somewhat arbitrary; taken from
                                                internet line length conventions --
                                                   PILEN    1024
                                                   TAGLVL   100
                                                   TAGLEN   2100
                                                   GRPGTCNT 150
                                                   GRPCNT   64
                                        
                                        FEATURES
                                          MINIMIZE
                                            DATATAG  NO
                                            OMITTAG  YES
                                            RANK     NO
                                            SHORTTAG YES
                                          LINK
                                            SIMPLE   NO
                                            IMPLICIT NO
                                            EXPLICIT NO
                                          OTHER
                                            CONCUR   NO
                                            SUBDOC   NO
                                            FORMAL   YES
                                          APPINFO    "SDA"  -- conforming SGML Document Access application
                                                  --
                                        &gt;
                                        &lt;!--
                                              $Id: html.decl,v 1.17 1995/06/08 14:59:32 connolly Exp $
                                        
                                              Author: Daniel W. Connolly &lt;connolly@w3.org&gt;
                                        
                                              See also: http://www.w3.org/hypertext/WWW/MarkUp/MarkUp.html
                                         --&gt;
                                        
                                        9.6. Sample SGML Open Entity Catalog for HTML
                                        
                                           The SGML standard describes an "entity manager" as the portion or
                                           component of an SGML system that maps SGML entities into the actual
                                           storage model (e.g., the file system). The standard itself does not
                                        
                                        
                                        
                                        Berners-Lee &amp;  Connolly      Standards Track                    [Page 65]
                                        
                                        RFC 1866            Hypertext Markup Language - 2.0        November 1995
                                        
                                        
                                           define a particular mapping methodology or notation.
                                        
                                           To assist the interoperability among various SGML tools and systems,
                                           the SGML Open consortium has passed a technical resolution that
                                           defines a format for an application-independent entity catalog that
                                           maps external identifiers and/or entity names to file names.
                                        
                                           Each entry in the catalog associates a storage object identifier
                                           (such as a file name) with information about the external entity that
                                           appears in the SGML document. In addition to entries that associate
                                           public identifiers, a catalog entry can associate an entity name with
                                           a storage object identifier. For example, the following are possible
                                           catalog entries:
                                        
                                              -- catalog: SGML Open style entity catalog for HTML --
                                              -- $Id: catalog,v 1.3 1995/09/21 23:30:23 connolly Exp $ --
                                        
                                              -- Ways to refer to Level 2: most general to most specific --
                                        PUBLIC  "-//IETF//DTD HTML//EN"                 html.dtd
                                        PUBLIC  "-//IETF//DTD HTML 2.0//EN"             html.dtd
                                        PUBLIC  "-//IETF//DTD HTML Level 2//EN"         html.dtd
                                        PUBLIC  "-//IETF//DTD HTML 2.0 Level 2//EN"     html.dtd
                                        
                                              -- Ways to refer to Level 1: most general to most specific --
                                        PUBLIC  "-//IETF//DTD HTML Level 1//EN"         html-1.dtd
                                        PUBLIC  "-//IETF//DTD HTML 2.0 Level 1//EN"     html-1.dtd
                                        
                                              -- Ways to refer to
                                                    Strict Level 2: most general to most specific --
                                        PUBLIC  "-//IETF//DTD HTML Strict//EN"                  html-s.dtd
                                        PUBLIC  "-//IETF//DTD HTML 2.0 Strict//EN"              html-s.dtd
                                        PUBLIC  "-//IETF//DTD HTML Strict Level 2//EN"          html-s.dtd
                                        PUBLIC  "-//IETF//DTD HTML 2.0 Strict Level 2//EN"      html-s.dtd
                                        
                                              -- Ways to refer to
                                                    Strict Level 1: most general to most specific --
                                        PUBLIC  "-//IETF//DTD HTML Strict Level 1//EN"          html-1s.dtd
                                        PUBLIC  "-//IETF//DTD HTML 2.0 Strict Level 1//EN"      html-1s.dtd
                                        
                                              -- ISO latin 1 entity set for HTML --
                                        PUBLIC  "ISO 8879-1986//ENTITIES Added Latin 1//EN//HTML" ISOlat1\
                                        sgml
                                        
                                        9.7. Character Entity Sets
                                        
                                           The HTML DTD defines the following entities. They represent
                                           particular graphic characters which have special meanings in places
                                           in the markup, or may not be part of the character set available to
                                        
                                        
                                        
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                                           the writer.
                                        
                                        9.7.1. Numeric and Special Graphic Entity Set
                                        
                                           The following table lists each of the characters included from the
                                           Numeric and Special Graphic entity set, along with its name, syntax
                                           for use, and description. This list is derived from `ISO Standard
                                           8879:1986//ENTITIES Numeric and Special Graphic//EN'.  However, HTML
                                           does not include for the entire entity set -- only the entities
                                           listed below are included.
                                        
                                            GLYPH   NAME    SYNTAX  DESCRIPTION
                                            &lt;       lt      &lt;    Less than sign
                                            &gt;       gt      &gt;    Greater than signn
                                            &amp;        amp     &amp;   Ampersand
                                            "       quot    "  Double quote sign
                                        
                                        9.7.2. ISO Latin 1 Character Entity Set
                                        
                                           The following public text lists each of the characters specified in
                                           the Added Latin 1 entity set, along with its name, syntax for use,
                                           and description. This list is derived from ISO Standard
                                           8879:1986//ENTITIES Added Latin 1//EN. HTML includes the entire
                                           entity set.
                                        
                                        &lt;!-- (C) International Organization for Standardization 1986
                                            Permission to copy in any form is granted for use with
                                            conforming SGML systems and applications as defined in
                                            ISO 8879, provided this notice is included in all copies.
                                        --&gt;
                                        &lt;!-- Character entity set. Typical invocation:
                                            &lt;!ENTITY % ISOlat1 PUBLIC
                                               "ISO 8879-1986//ENTITIES Added Latin 1//EN//HTML"&gt;
                                            %ISOlat1;
                                        --&gt;
                                        &lt;!--    Modified for use in HTML
                                              $Id: ISOlat1.sgml,v 1.2 1994/11/30 23:45:12 connolly Exp $ --&gt;
                                        &lt;!ENTITY AElig  CDATA "Æ" -- capital AE diphthong (ligature) --&gt;
                                        &lt;!ENTITY Aacute CDATA "Á" -- capital A, acute accent --&gt;
                                        &lt;!ENTITY Acirc  CDATA "Â" -- capital A, circumflex accent --&gt;
                                        &lt;!ENTITY Agrave CDATA "À" -- capital A, grave accent --&gt;
                                        &lt;!ENTITY Aring  CDATA "Å" -- capital A, ring --&gt;
                                        &lt;!ENTITY Atilde CDATA "Ã" -- capital A, tilde --&gt;
                                        &lt;!ENTITY Auml   CDATA "Ä" -- capital A, dieresis or umlaut mark --&gt;
                                        &lt;!ENTITY Ccedil CDATA "Ç" -- capital C, cedilla --&gt;
                                        &lt;!ENTITY ETH    CDATA "Ð" -- capital Eth, Icelandic --&gt;
                                        &lt;!ENTITY Eacute CDATA "É" -- capital E, acute accent --&gt;
                                        &lt;!ENTITY Ecirc  CDATA "Ê" -- capital E, circumflex accent --&gt;
                                        
                                        
                                        
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                                        &lt;!ENTITY Egrave CDATA "È" -- capital E, grave accent --&gt;
                                        &lt;!ENTITY Euml   CDATA "Ë" -- capital E, dieresis or umlaut mark --&gt;
                                        &lt;!ENTITY Iacute CDATA "Í" -- capital I, acute accent --&gt;
                                        &lt;!ENTITY Icirc  CDATA "Î" -- capital I, circumflex accent --&gt;
                                        &lt;!ENTITY Igrave CDATA "Ì" -- capital I, grave accent --&gt;
                                        &lt;!ENTITY Iuml   CDATA "Ï" -- capital I, dieresis or umlaut mark --&gt;
                                        &lt;!ENTITY Ntilde CDATA "Ñ" -- capital N, tilde --&gt;
                                        &lt;!ENTITY Oacute CDATA "Ó" -- capital O, acute accent --&gt;
                                        &lt;!ENTITY Ocirc  CDATA "Ô" -- capital O, circumflex accent --&gt;
                                        &lt;!ENTITY Ograve CDATA "Ò" -- capital O, grave accent --&gt;
                                        &lt;!ENTITY Oslash CDATA "Ø" -- capital O, slash --&gt;
                                        &lt;!ENTITY Otilde CDATA "Õ" -- capital O, tilde --&gt;
                                        &lt;!ENTITY Ouml   CDATA "Ö" -- capital O, dieresis or umlaut mark --&gt;
                                        &lt;!ENTITY THORN  CDATA "Þ" -- capital THORN, Icelandic --&gt;
                                        &lt;!ENTITY Uacute CDATA "Ú" -- capital U, acute accent --&gt;
                                        &lt;!ENTITY Ucirc  CDATA "Û" -- capital U, circumflex accent --&gt;
                                        &lt;!ENTITY Ugrave CDATA "Ù" -- capital U, grave accent --&gt;
                                        &lt;!ENTITY Uuml   CDATA "Ü" -- capital U, dieresis or umlaut mark --&gt;
                                        &lt;!ENTITY Yacute CDATA "Ý" -- capital Y, acute accent --&gt;
                                        &lt;!ENTITY aacute CDATA "á" -- small a, acute accent --&gt;
                                        &lt;!ENTITY acirc  CDATA "â" -- small a, circumflex accent --&gt;
                                        &lt;!ENTITY aelig  CDATA "æ" -- small ae diphthong (ligature) --&gt;
                                        &lt;!ENTITY agrave CDATA "à" -- small a, grave accent --&gt;
                                        &lt;!ENTITY aring  CDATA "å" -- small a, ring --&gt;
                                        &lt;!ENTITY atilde CDATA "ã" -- small a, tilde --&gt;
                                        &lt;!ENTITY auml   CDATA "ä" -- small a, dieresis or umlaut mark --&gt;
                                        &lt;!ENTITY ccedil CDATA "ç" -- small c, cedilla --&gt;
                                        &lt;!ENTITY eacute CDATA "é" -- small e, acute accent --&gt;
                                        &lt;!ENTITY ecirc  CDATA "ê" -- small e, circumflex accent --&gt;
                                        &lt;!ENTITY egrave CDATA "è" -- small e, grave accent --&gt;
                                        &lt;!ENTITY eth    CDATA "ð" -- small eth, Icelandic --&gt;
                                        &lt;!ENTITY euml   CDATA "ë" -- small e, dieresis or umlaut mark --&gt;
                                        &lt;!ENTITY iacute CDATA "í" -- small i, acute accent --&gt;
                                        &lt;!ENTITY icirc  CDATA "î" -- small i, circumflex accent --&gt;
                                        &lt;!ENTITY igrave CDATA "ì" -- small i, grave accent --&gt;
                                        &lt;!ENTITY iuml   CDATA "ï" -- small i, dieresis or umlaut mark --&gt;
                                        &lt;!ENTITY ntilde CDATA "ñ" -- small n, tilde --&gt;
                                        &lt;!ENTITY oacute CDATA "ó" -- small o, acute accent --&gt;
                                        &lt;!ENTITY ocirc  CDATA "ô" -- small o, circumflex accent --&gt;
                                        &lt;!ENTITY ograve CDATA "ò" -- small o, grave accent --&gt;
                                        &lt;!ENTITY oslash CDATA "ø" -- small o, slash --&gt;
                                        &lt;!ENTITY otilde CDATA "õ" -- small o, tilde --&gt;
                                        &lt;!ENTITY ouml   CDATA "ö" -- small o, dieresis or umlaut mark --&gt;
                                        &lt;!ENTITY szlig  CDATA "ß" -- small sharp s, German (sz ligature)-&gt;
                                        &lt;!ENTITY thorn  CDATA "þ" -- small thorn, Icelandic --&gt;
                                        &lt;!ENTITY uacute CDATA "ú" -- small u, acute accent --&gt;
                                        &lt;!ENTITY ucirc  CDATA "û" -- small u, circumflex accent --&gt;
                                        &lt;!ENTITY ugrave CDATA "ù" -- small u, grave accent --&gt;
                                        
                                        
                                        
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                                        &lt;!ENTITY uuml   CDATA "ü" -- small u, dieresis or umlaut mark --&gt;
                                        &lt;!ENTITY yacute CDATA "ý" -- small y, acute accent --&gt;
                                        &lt;!ENTITY yuml   CDATA "ÿ" -- small y, dieresis or umlaut mark --&gt;
                                        
                                        10. Security Considerations
                                        
                                           Anchors, embedded images, and all other elements which contain URIs
                                           as parameters may cause the URI to be dereferenced in response to
                                           user input. In this case, the security considerations of [URL] apply.
                                        
                                           The widely deployed methods for submitting forms requests -- HTTP and
                                           SMTP -- provide little assurance of confidentiality.  Information
                                           providers who request sensitive information via forms -- especially
                                           by way of the `PASSWORD' type input field (see 8.1.2, "Input Field:
                                           INPUT") -- should be aware and make their users aware of the lack of
                                           confidentiality.
                                        
                                        11. References
                                        
                                            [URI]
                                                 Berners-Lee, T., "Universal Resource Identifiers in WWW:
                                                 A Unifying Syntax for the Expression of Names and
                                                 Addresses of Objects on the Network as used in the
                                                 World- Wide Web",  RFC 1630, CERN, June 1994.
                                                 &lt;URL:ftp://ds.internic.net/rfc/rfc1630.txt&gt;
                                        
                                            [URL]
                                                 Berners-Lee, T., Masinter, L., and M. McCahill, "Uniform
                                                 Resource Locators (URL)", RFC 1738, CERN, Xerox PARC,
                                                 University of Minnesota, December 1994.
                                                 &lt;URL:ftp://ds.internic.net/rfc/rfc1738.txt&gt;
                                        
                                            [HTTP]
                                                 Berners-Lee, T., Fielding, R., and H. Frystyk Nielsen,
                                                 "Hypertext Transfer Protocol - HTTP/1.0", Work in
                                                 Progress, MIT, UC Irvine, CERN, March 1995.
                                        
                                            [MIME]
                                                 Borenstein, N., and N. Freed. "MIME (Multipurpose
                                                 Internet Mail Extensions) Part One: Mechanisms for
                                                 Specifying and Describing the Format of Internet Message
                                                 Bodies", RFC 1521, Bellcore, Innosoft, September 1993.
                                                 &lt;URL:ftp://ds.internic.net/rfc/rfc1521.txt&gt;
                                        
                                            [RELURL]
                                                 Fielding, R., "Relative Uniform Resource Locators", RFC
                                                 1808, June 1995
                                                 &lt;URL:ftp://ds.internic.net/rfc/rfc1808.txt&gt;
                                        
                                        
                                        
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                                            [GOLD90]
                                                 Goldfarb, C., "The SGML Handbook", Y. Rubinsky, Ed.,
                                                 Oxford University Press, 1990.
                                        
                                            [DEXTER]
                                                 Frank Halasz and Mayer Schwartz, "The Dexter Hypertext
                                                 Reference Model", Communications of the ACM, pp.
                                                 30-39, vol. 37 no. 2, Feb 1994.
                                        
                                            [IMEDIA]
                                                 Postel, J., "Media Type Registration Procedure",
                                                 RFC 1590, USC/Information Sciences Institute, March 1994.
                                                 &lt;URL:ftp://ds.internic.net/rfc/rfc1590.txt&gt;
                                        
                                            [IANA]
                                                 Reynolds, J., and J. Postel, "Assigned Numbers", STD 2,
                                                 RFC 1700, USC/Information Sciecnes Institute, October
                                                 1994.  &lt;URL:ftp://ds.internic.net/rfc/rfc1700.txt&gt;
                                        
                                            [SQ91]
                                                 SoftQuad. "The SGML Primer", 3rd ed., SoftQuad Inc.,
                                                 1991. &lt;URL:http://www.sq.com/&gt;
                                        
                                            [ISO-646]
                                                 ISO/IEC 646:1991 Information technology -- ISO 7-bit
                                                 coded character set for information interchange
                                                 &lt;URL:http://www.iso.ch/cate/d4777.html&gt;
                                        
                                            [ISO-10646]
                                                 ISO/IEC 10646-1:1993 Information technology -- Universal
                                                 Multiple-Octet Coded Character Set (UCS) -- Part 1:
                                                 Architecture and Basic Multilingual Plane
                                                 &lt;URL:http://www.iso.ch/cate/d18741.html&gt;
                                        
                                            [ISO-8859-1]
                                                 ISO 8859. International Standard -- Information
                                                 Processing -- 8-bit Single-Byte Coded Graphic Character
                                                 Sets -- Part 1: Latin Alphabet No. 1, ISO 8859-1:1987.
                                                 &lt;URL:http://www.iso.ch/cate/d16338.html&gt;
                                        
                                            [SGML]
                                                 ISO 8879. Information Processing -- Text and Office
                                                 Systems - Standard Generalized Markup Language (SGML),
                                                 1986. &lt;URL:http://www.iso.ch/cate/d16387.html&gt;
                                        
                                        
                                        
                                        
                                        
                                        
                                        
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                                        12. Acknowledgments
                                        
                                           The HTML document type was designed by Tim Berners-Lee at CERN as
                                           part of the 1990 World Wide Web project. In 1992, Dan Connolly wrote
                                           the HTML Document Type Definition (DTD) and a brief HTML
                                           specification.
                                        
                                           Since 1993, a wide variety of Internet participants have contributed
                                           to the evolution of HTML, which has included the addition of in-line
                                           images introduced by the NCSA Mosaic software for WWW. Dave Raggett
                                           played an important role in deriving the forms material from the
                                           HTML+ specification.
                                        
                                           Dan Connolly and Karen Olson Muldrow rewrote the HTML Specification
                                           in 1994. The document was then edited by the HTML working group as a
                                           whole, with updates being made by Eric Schieler, Mike Knezovich, and
                                           Eric W. Sink at Spyglass, Inc.  Finally, Roy Fielding restructured
                                           the entire draft into its current form.
                                        
                                           Special thanks to the many active participants in the HTML working
                                           group, too numerous to list individually, without whom there would be
                                           no standards process and no standard. That this document approaches
                                           its objective of carefully converging a description of current
                                           practice and formalization of HTML's relationship to SGML is a
                                           tribute to their effort.
                                        
                                        12.1. Authors' Addresses
                                        
                                           Tim Berners-Lee
                                           Director, W3 Consortium
                                           MIT Laboratory for Computer Science
                                           545 Technology Square
                                           Cambridge, MA 02139, U.S.A.
                                        
                                           Phone: +1 (617) 253 9670
                                           Fax: +1 (617) 258 8682
                                           EMail: timbl@w3.org
                                        
                                        
                                           Daniel W. Connolly
                                           Research Technical Staff, W3 Consortium
                                           MIT Laboratory for Computer Science
                                           545 Technology Square
                                           Cambridge, MA 02139, U.S.A.
                                        
                                           Phone: +1 (617) 258 8682
                                           EMail: connolly@w3.org
                                           URI: http://www.w3.org/hypertext/WWW/People/Connolly/
                                        
                                        
                                        
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                                        13. The HTML Coded Character Set
                                        
                                           This list details the code positions and characters of the HTML
                                           document character set, specified in 9.5, "SGML Declaration for
                                           HTML". This coded character set is based on [ISO-8859-1].
                                        
                                            REFERENCE       DESCRIPTION
                                            --------------  -----------
                                             -    Unused
                                                  Horizontal tab
                                            
                                                  Line feed
                                             -    Unused
                                            
                                                  Carriage Return
                                             -    Unused
                                                    Space
                                            !           Exclamation mark
                                            "           Quotation mark
                                            #           Number sign
                                            $           Dollar sign
                                            %           Percent sign
                                            &amp;           Ampersand
                                            '           Apostrophe
                                            (           Left parenthesis
                                            )           Right parenthesis
                                            *           Asterisk
                                            +           Plus sign
                                            ,           Comma
                                            -           Hyphen
                                            .           Period (fullstop)
                                            /           Solidus (slash)
                                            0 - 9   Digits 0-9
                                            :           Colon
                                            ;           Semi-colon
                                            &lt;           Less than
                                            =           Equals sign
                                            &gt;           Greater than
                                            ?           Question mark
                                            @           Commercial at
                                            A - Z   Letters A-Z
                                            [           Left square bracket
                                            \           Reverse solidus (backslash)
                                            ]           Right square bracket
                                            ^           Caret
                                            _           Horizontal bar (underscore)
                                            `           Acute accent
                                            a - z  Letters a-z
                                            {          Left curly brace
                                            |          Vertical bar
                                        
                                        
                                        
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                                            }          Right curly brace
                                            ~          Tilde
                                             - Ÿ Unused
                                                       Non-breaking Space
                                            ¡          Inverted exclamation
                                            ¢          Cent sign
                                            £          Pound sterling
                                            ¤          General currency sign
                                            ¥          Yen sign
                                            ¦          Broken vertical bar
                                            §          Section sign
                                            ¨          Umlaut (dieresis)
                                            ©          Copyright
                                            ª          Feminine ordinal
                                            «          Left angle quote, guillemotleft
                                            ¬          Not sign
                                            ­          Soft hyphen
                                            ®          Registered trademark
                                            ¯          Macron accent
                                            °          Degree sign
                                            ±          Plus or minus
                                            ²          Superscript two
                                            ³          Superscript three
                                            ´          Acute accent
                                            µ          Micro sign
                                            ¶          Paragraph sign
                                            ·          Middle dot
                                            ¸          Cedilla
                                            ¹          Superscript one
                                            º          Masculine ordinal
                                            »          Right angle quote, guillemotright
                                            ¼          Fraction one-fourth
                                            ½          Fraction one-half
                                            ¾          Fraction three-fourths
                                            ¿          Inverted question mark
                                            À          Capital A, grave accent
                                            Á          Capital A, acute accent
                                            Â          Capital A, circumflex accent
                                            Ã          Capital A, tilde
                                            Ä          Capital A, dieresis or umlaut mark
                                            Å          Capital A, ring
                                            Æ          Capital AE dipthong (ligature)
                                            Ç          Capital C, cedilla
                                            È          Capital E, grave accent
                                            É          Capital E, acute accent
                                            Ê          Capital E, circumflex accent
                                            Ë          Capital E, dieresis or umlaut mark
                                            Ì          Capital I, grave accent
                                        
                                        
                                        
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                                            Í          Capital I, acute accent
                                            Î          Capital I, circumflex accent
                                            Ï          Capital I, dieresis or umlaut mark
                                            Ð          Capital Eth, Icelandic
                                            Ñ          Capital N, tilde
                                            Ò          Capital O, grave accent
                                            Ó          Capital O, acute accent
                                            Ô          Capital O, circumflex accent
                                            Õ          Capital O, tilde
                                            Ö          Capital O, dieresis or umlaut mark
                                            ×          Multiply sign
                                            Ø          Capital O, slash
                                            Ù          Capital U, grave accent
                                            Ú          Capital U, acute accent
                                            Û          Capital U, circumflex accent
                                            Ü          Capital U, dieresis or umlaut mark
                                            Ý          Capital Y, acute accent
                                            Þ          Capital THORN, Icelandic
                                            ß          Small sharp s, German (sz ligature)
                                            à          Small a, grave accent
                                            á          Small a, acute accent
                                            â          Small a, circumflex accent
                                            ã          Small a, tilde
                                            ä          Small a, dieresis or umlaut mark
                                            å          Small a, ring
                                            æ          Small ae dipthong (ligature)
                                            ç          Small c, cedilla
                                            è          Small e, grave accent
                                            é          Small e, acute accent
                                            ê          Small e, circumflex accent
                                            ë          Small e, dieresis or umlaut mark
                                            ì          Small i, grave accent
                                            í          Small i, acute accent
                                            î          Small i, circumflex accent
                                            ï          Small i, dieresis or umlaut mark
                                            ð          Small eth, Icelandic
                                            ñ          Small n, tilde
                                            ò          Small o, grave accent
                                            ó          Small o, acute accent
                                            ô          Small o, circumflex accent
                                            õ          Small o, tilde
                                            ö          Small o, dieresis or umlaut mark
                                            ÷          Division sign
                                            ø          Small o, slash
                                            ù          Small u, grave accent
                                            ú          Small u, acute accent
                                            û          Small u, circumflex accent
                                            ü          Small u, dieresis or umlaut mark
                                        
                                        
                                        
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                                            ý          Small y, acute accent
                                            þ          Small thorn, Icelandic
                                            ÿ          Small y, dieresis or umlaut mark
                                        
                                        14. Proposed Entities
                                        
                                           The HTML DTD references the "Added Latin 1" entity set, which only
                                           supplies named entities for a subset of the non-ASCII characters in
                                           [ISO-8859-1], namely the accented characters. The following entities
                                           should be supported so that all ISO 8859-1 characters may only be
                                           referenced symbolically. The names for these entities are taken from
                                           the appendixes of [SGML].
                                        
                                            &lt;!ENTITY nbsp   CDATA " " -- no-break space --&gt;
                                            &lt;!ENTITY iexcl  CDATA "¡" -- inverted exclamation mark --&gt;
                                            &lt;!ENTITY cent   CDATA "¢" -- cent sign --&gt;
                                            &lt;!ENTITY pound  CDATA "£" -- pound sterling sign --&gt;
                                            &lt;!ENTITY curren CDATA "¤" -- general currency sign --&gt;
                                            &lt;!ENTITY yen    CDATA "¥" -- yen sign --&gt;
                                            &lt;!ENTITY brvbar CDATA "¦" -- broken (vertical) bar --&gt;
                                            &lt;!ENTITY sect   CDATA "§" -- section sign --&gt;
                                            &lt;!ENTITY uml    CDATA "¨" -- umlaut (dieresis) --&gt;
                                            &lt;!ENTITY copy   CDATA "©" -- copyright sign --&gt;
                                            &lt;!ENTITY ordf   CDATA "ª" -- ordinal indicator, feminine --&gt;
                                            &lt;!ENTITY laquo  CDATA "«" -- angle quotation mark, left --&gt;
                                            &lt;!ENTITY not    CDATA "¬" -- not sign --&gt;
                                            &lt;!ENTITY shy    CDATA "­" -- soft hyphen --&gt;
                                            &lt;!ENTITY reg    CDATA "®" -- registered sign --&gt;
                                            &lt;!ENTITY macr   CDATA "¯" -- macron --&gt;
                                            &lt;!ENTITY deg    CDATA "°" -- degree sign --&gt;
                                            &lt;!ENTITY plusmn CDATA "±" -- plus-or-minus sign --&gt;
                                            &lt;!ENTITY sup2   CDATA "²" -- superscript two --&gt;
                                            &lt;!ENTITY sup3   CDATA "³" -- superscript three --&gt;
                                            &lt;!ENTITY acute  CDATA "´" -- acute accent --&gt;
                                            &lt;!ENTITY micro  CDATA "µ" -- micro sign --&gt;
                                            &lt;!ENTITY para   CDATA "¶" -- pilcrow (paragraph sign) --&gt;
                                            &lt;!ENTITY middot CDATA "·" -- middle dot --&gt;
                                            &lt;!ENTITY cedil  CDATA "¸" -- cedilla --&gt;
                                            &lt;!ENTITY sup1   CDATA "¹" -- superscript one --&gt;
                                            &lt;!ENTITY ordm   CDATA "º" -- ordinal indicator, masculine --&gt;
                                            &lt;!ENTITY raquo  CDATA "»" -- angle quotation mark, right --&gt;
                                            &lt;!ENTITY frac14 CDATA "¼" -- fraction one-quarter --&gt;
                                            &lt;!ENTITY frac12 CDATA "½" -- fraction one-half --&gt;
                                            &lt;!ENTITY frac34 CDATA "¾" -- fraction three-quarters --&gt;
                                            &lt;!ENTITY iquest CDATA "¿" -- inverted question mark --&gt;
                                            &lt;!ENTITY Agrave CDATA "À" -- capital A, grave accent --&gt;
                                            &lt;!ENTITY Aacute CDATA "Á" -- capital A, acute accent --&gt;
                                            &lt;!ENTITY Acirc  CDATA "Â" -- capital A, circumflex accent --&gt;
                                        
                                        
                                        
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                                        RFC 1866            Hypertext Markup Language - 2.0        November 1995
                                        
                                        
                                            &lt;!ENTITY Atilde CDATA "Ã" -- capital A, tilde --&gt;
                                            &lt;!ENTITY Auml   CDATA "Ä" -- capital A, dieresis or umlaut mark --&gt;
                                            &lt;!ENTITY Aring  CDATA "Å" -- capital A, ring --&gt;
                                            &lt;!ENTITY AElig  CDATA "Æ" -- capital AE diphthong (ligature) --&gt;
                                            &lt;!ENTITY Ccedil CDATA "Ç" -- capital C, cedilla --&gt;
                                            &lt;!ENTITY Egrave CDATA "È" -- capital E, grave accent --&gt;
                                            &lt;!ENTITY Eacute CDATA "É" -- capital E, acute accent --&gt;
                                            &lt;!ENTITY Ecirc  CDATA "Ê" -- capital E, circumflex accent --&gt;
                                            &lt;!ENTITY Euml   CDATA "Ë" -- capital E, dieresis or umlaut mark --&gt;
                                            &lt;!ENTITY Igrave CDATA "Ì" -- capital I, grave accent --&gt;
                                            &lt;!ENTITY Iacute CDATA "Í" -- capital I, acute accent --&gt;
                                            &lt;!ENTITY Icirc  CDATA "Î" -- capital I, circumflex accent --&gt;
                                            &lt;!ENTITY Iuml   CDATA "Ï" -- capital I, dieresis or umlaut mark --&gt;
                                            &lt;!ENTITY ETH    CDATA "Ð" -- capital Eth, Icelandic --&gt;
                                            &lt;!ENTITY Ntilde CDATA "Ñ" -- capital N, tilde --&gt;
                                            &lt;!ENTITY Ograve CDATA "Ò" -- capital O, grave accent --&gt;
                                            &lt;!ENTITY Oacute CDATA "Ó" -- capital O, acute accent --&gt;
                                            &lt;!ENTITY Ocirc  CDATA "Ô" -- capital O, circumflex accent --&gt;
                                            &lt;!ENTITY Otilde CDATA "Õ" -- capital O, tilde --&gt;
                                            &lt;!ENTITY Ouml   CDATA "Ö" -- capital O, dieresis or umlaut mark --&gt;
                                            &lt;!ENTITY times  CDATA "×" -- multiply sign --&gt;
                                            &lt;!ENTITY Oslash CDATA "Ø" -- capital O, slash --&gt;
                                            &lt;!ENTITY Ugrave CDATA "Ù" -- capital U, grave accent --&gt;
                                            &lt;!ENTITY Uacute CDATA "Ú" -- capital U, acute accent --&gt;
                                            &lt;!ENTITY Ucirc  CDATA "Û" -- capital U, circumflex accent --&gt;
                                            &lt;!ENTITY Uuml   CDATA "Ü" -- capital U, dieresis or umlaut mark --&gt;
                                            &lt;!ENTITY Yacute CDATA "Ý" -- capital Y, acute accent --&gt;
                                            &lt;!ENTITY THORN  CDATA "Þ" -- capital THORN, Icelandic --&gt;
                                            &lt;!ENTITY szlig  CDATA "ß" -- small sharp s, German (sz ligature) --&gt;
                                            &lt;!ENTITY agrave CDATA "à" -- small a, grave accent --&gt;
                                            &lt;!ENTITY aacute CDATA "á" -- small a, acute accent --&gt;
                                            &lt;!ENTITY acirc  CDATA "â" -- small a, circumflex accent --&gt;
                                            &lt;!ENTITY atilde CDATA "ã" -- small a, tilde --&gt;
                                            &lt;!ENTITY auml   CDATA "ä" -- small a, dieresis or umlaut mark --&gt;
                                            &lt;!ENTITY aring  CDATA "å" -- small a, ring --&gt;
                                            &lt;!ENTITY aelig  CDATA "æ" -- small ae diphthong (ligature) --&gt;
                                            &lt;!ENTITY ccedil CDATA "ç" -- small c, cedilla --&gt;
                                            &lt;!ENTITY egrave CDATA "è" -- small e, grave accent --&gt;
                                            &lt;!ENTITY eacute CDATA "é" -- small e, acute accent --&gt;
                                            &lt;!ENTITY ecirc  CDATA "ê" -- small e, circumflex accent --&gt;
                                            &lt;!ENTITY euml   CDATA "ë" -- small e, dieresis or umlaut mark --&gt;
                                            &lt;!ENTITY igrave CDATA "ì" -- small i, grave accent --&gt;
                                            &lt;!ENTITY iacute CDATA "í" -- small i, acute accent --&gt;
                                            &lt;!ENTITY icirc  CDATA "î" -- small i, circumflex accent --&gt;
                                            &lt;!ENTITY iuml   CDATA "ï" -- small i, dieresis or umlaut mark --&gt;
                                            &lt;!ENTITY eth    CDATA "ð" -- small eth, Icelandic --&gt;
                                            &lt;!ENTITY ntilde CDATA "ñ" -- small n, tilde --&gt;
                                            &lt;!ENTITY ograve CDATA "ò" -- small o, grave accent --&gt;
                                        
                                        
                                        
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                                        RFC 1866            Hypertext Markup Language - 2.0        November 1995
                                        
                                        
                                            &lt;!ENTITY oacute CDATA "ó" -- small o, acute accent --&gt;
                                            &lt;!ENTITY ocirc  CDATA "ô" -- small o, circumflex accent --&gt;
                                            &lt;!ENTITY otilde CDATA "õ" -- small o, tilde --&gt;
                                            &lt;!ENTITY ouml   CDATA "ö" -- small o, dieresis or umlaut mark --&gt;
                                            &lt;!ENTITY divide CDATA "÷" -- divide sign --&gt;
                                            &lt;!ENTITY oslash CDATA "ø" -- small o, slash --&gt;
                                            &lt;!ENTITY ugrave CDATA "ù" -- small u, grave accent --&gt;
                                            &lt;!ENTITY uacute CDATA "ú" -- small u, acute accent --&gt;
                                            &lt;!ENTITY ucirc  CDATA "û" -- small u, circumflex accent --&gt;
                                            &lt;!ENTITY uuml   CDATA "ü" -- small u, dieresis or umlaut mark --&gt;
                                            &lt;!ENTITY yacute CDATA "ý" -- small y, acute accent --&gt;
                                            &lt;!ENTITY thorn  CDATA "þ" -- small thorn, Icelandic --&gt;
                                            &lt;!ENTITY yuml   CDATA "ÿ" -- small y, dieresis or umlaut mark --&gt;
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                                        
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                                        </OPTION>
                                      </SELECT>
                                    </FORM>
                                  </BLOCKQUOTE>
                                </LI>
                              </MENU>
                            </LI>
                          </MENU>
                        </LI>
                      </DIR>
                    </LI>
                  </DIR>
                </OL>
              </OL>
            </UL>
          </UL>
        </DD>
      </DL>
      <H1>Heading</H1>
    </FORM>
    <FORM>
       element contains a sequence of input elements, along
        with document structuring elements. The attributes are:
      
        ACTION
         specifies the action URI for the form. The action URI of
         a form defaults to the base URI of the document (see 7,
         "Hyperlinks").
      
        METHOD
         selects a method of accessing the action URI. The set of
         applicable methods is a function of the scheme of the
         action URI of the form. See 8.2.2, "Query Forms:
         METHOD=GET" and 8.2.3, "Forms with Side-Effects:
         METHOD=POST".
      
        ENCTYPE
         specifies the media type used to encode the name/value
         pairs for transport, in case the protocol does not
         itself impose a format. See 8.2.1, "The form-urlencoded
         Media Type".
      
      8.1.2. Input Field: INPUT
      
        The 
      <INPUT/>
       element represents a field for user input. The TYPE
        attribute discriminates between several variations of fields.
      
      
      
      
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      RFC 1866            Hypertext Markup Language - 2.0        November 1995
      
      
        The 
      <INPUT/>
       element has a number of attributes. The set of applicable
        attributes depends on the value of the TYPE attribute.
      
      8.1.2.1. Text Field: INPUT TYPE=TEXT
      
        The default value of the TYPE attribute is `TEXT', indicating a
        single line text entry field. (Use the 
      <TEXTAREA> element for multi-
        line text fields.)
      
        Required attributes are:
      
        NAME
         name for the form field corresponding to this element.
      
        The optional attributes are:
      
        MAXLENGTH
         constrains the number of characters that can be entered
         into a text input field. If the value of MAXLENGTH is
         greater the the value of the SIZE attribute, the field
         should scroll appropriately. The default number of
         characters is unlimited.
      
        SIZE
         specifies the amount of display space allocated to this
         input field according to its type. The default depends
         on the user agent.
      
        VALUE
         The initial value of the field.
      
        For example:
      
      &lt;p&gt;Street Address: &lt;input name=street&gt;&lt;br&gt;
      Postal City code: &lt;input name=city size=16 maxlength=16&gt;&lt;br&gt;
      Zip Code: &lt;input name=zip size=10 maxlength=10 value="99999-9999"&gt;&lt;br&gt;
      
      8.1.2.2. Password Field: INPUT TYPE=PASSWORD
      
        An &lt;INPUT&gt; element with `TYPE=PASSWORD' is a text field as above,
        except that the value is obscured as it is entered. (see also: 10,
        "Security Considerations").
      
        For example:
      
      &lt;p&gt;Name: &lt;input name=login&gt; Password: &lt;input type=password name=passwd&gt;
      
      
      
      
      
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      RFC 1866            Hypertext Markup Language - 2.0        November 1995
      
      
      8.1.2.3. Check Box: INPUT TYPE=CHECKBOX
      
        An &lt;INPUT&gt; element with `TYPE=CHECKBOX' represents a boolean choice.
        A set of such elements with the same name represents an n-of-many
        choice field. Required attributes are:
      
        NAME
         symbolic name for the form field corresponding to this
         element or group of elements.
      
        VALUE
         The portion of the value of the field contributed by
         this element.
      
        Optional attributes are:
      
        CHECKED
         indicates that the initial state is on.
      
        For example:
      
       &lt;p&gt;What flavors do you like?
       &lt;input type=checkbox name=flavor value=vanilla&gt;Vanilla&lt;br&gt;
       &lt;input type=checkbox name=flavor value=strawberry&gt;Strawberry&lt;br&gt;
       &lt;input type=checkbox name=flavor value=chocolate checked&gt;Chocolate&lt;br&gt;
      
      8.1.2.4. Radio Button: INPUT TYPE=RADIO
      
        An &lt;INPUT&gt; element with `TYPE=RADIO' represents a boolean choice. A
        set of such elements with the same name represents a 1-of-many choice
        field. The NAME and VALUE attributes are required as for check boxes.
        Optional attributes are:
      
        CHECKED
         indicates that the initial state is on.
        At all times, exactly one of the radio buttons in a set is checked.
        If none of the &lt;INPUT&gt; elements of a set of radio buttons specifies
        `CHECKED', then the user agent must check the first radio button of
        the set initially.
      
        For example:
      
        &lt;p&gt;Which is your favorite?
        &lt;input type=radio name=flavor value=vanilla&gt;Vanilla&lt;br&gt;
        &lt;input type=radio name=flavor value=strawberry&gt;Strawberry&lt;br&gt;
        &lt;input type=radio name=flavor value=chocolate&gt;Chocolate&lt;br&gt;
      
      
      
      
      
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      RFC 1866            Hypertext Markup Language - 2.0        November 1995
      
      
      8.1.2.5. Image Pixel: INPUT TYPE=IMAGE
      
        An &lt;INPUT&gt; element with `TYPE=IMAGE' specifies an image resource to
        display, and allows input of two form fields: the x and y coordinate
        of a pixel chosen from the image. The names of the fields are the
        name of the field with `.x' and `.y' appended.  `TYPE=IMAGE' implies
        `TYPE=SUBMIT' processing; that is, when a pixel is chosen, the form
        as a whole is submitted.
      
        The NAME attribute is required as for other input fields. The SRC
        attribute is required and the ALIGN is optional as for the &lt;IMG&gt;
        element (see 5.10, "Image: IMG").
      
        For example:
      
        &lt;p&gt;Choose a point on the map:
        &lt;input type=image name=point src="map.gif"&gt;
      
      8.1.2.6. Hidden Field: INPUT TYPE=HIDDEN
      
        An &lt;INPUT&gt; element with `TYPE=HIDDEN' represents a hidden field.The
        user does not interact with this field; instead, the VALUE attribute
        specifies the value of the field. The NAME and VALUE attributes are
        required.
      
        For example:
      
        &lt;input type=hidden name=context value="l2k3j4l2k3j4l2k3j4lk23"&gt;
      
      8.1.2.7. Submit Button: INPUT TYPE=SUBMIT
      
        An &lt;INPUT&gt; element with `TYPE=SUBMIT' represents an input option,
        typically a button, that instructs the user agent to submit the form.
        Optional attributes are:
      
        NAME
         indicates that this element contributes a form field
         whose value is given by the VALUE attribute. If the NAME
         attribute is not present, this element does not
         contribute a form field.
      
        VALUE
         indicates a label for the input (button).
      
        You may submit this request internally:
        &lt;input type=submit name=recipient value=internal&gt;&lt;br&gt;
        or to the external world:
        &lt;input type=submit name=recipient value=world&gt;
      
      
      
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      RFC 1866            Hypertext Markup Language - 2.0        November 1995
      
      
      8.1.2.8. Reset Button: INPUT TYPE=RESET
      
        An &lt;INPUT&gt; element with `TYPE=RESET' represents an input option,
        typically a button, that instructs the user agent to reset the form's
        fields to their initial states. The VALUE attribute, if present,
        indicates a label for the input (button).
      
        When you are finished, you may submit this request:
        &lt;input type=submit&gt;&lt;br&gt;
        You may clear the form and start over at any time: &lt;input type=reset&gt;
      
      8.1.3. Selection: SELECT
      
        The &lt;SELECT&gt; element constrains the form field to an enumerated list
        of values. The values are given in &lt;OPTION&gt; elements.  Attributes
        are:
      
        MULTIPLE
         indicates that more than one option may be included in
         the value.
      
        NAME
         specifies the name of the form field.
      
        SIZE
         specifies the number of visible items. Select fields of
         size one are typically pop-down menus, whereas select
         fields with size greater than one are typically lists.
      
        For example:
      
        &lt;SELECT NAME="flavor"&gt;
        &lt;OPTION&gt;Vanilla
        &lt;OPTION&gt;Strawberry
        &lt;OPTION value="RumRasin"&gt;Rum and Raisin
        &lt;OPTION selected&gt;Peach and Orange
        &lt;/SELECT&gt;
      
        The initial state has the first option selected, unless a SELECTED
        attribute is present on any of the &lt;OPTION&gt; elements.
      
      8.1.3.1. Option: OPTION
      
        The Option element can only occur within a Select element. It
        represents one choice, and has the following attributes:
      
        SELECTED
         Indicates that this option is initially selected.
      
      
      
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      RFC 1866            Hypertext Markup Language - 2.0        November 1995
      
      
        VALUE
         indicates the value to be returned if this option is
         chosen. The field value defaults to the content of the
         &lt;OPTION&gt; element.
      
        The content of the &lt;OPTION&gt; element is presented to the user to
        represent the option. It is used as a returned value if the VALUE
        attribute is not present.
      
      8.1.4. Text Area: TEXTAREA
      
        The &lt;TEXTAREA&gt; element represents a multi-line text field.
        Attributes are:
      
        COLS
         the number of visible columns to display for the text
         area, in characters.
      
        NAME
         Specifies the name of the form field.
      
        ROWS
         The number of visible rows to display for the text area,
         in characters.
      
        For example:
      
        &lt;TEXTAREA NAME="address" ROWS=6 COLS=64&gt;
        HaL Computer Systems
        1315 Dell Avenue
        Campbell, California 95008</TEXTAREA>
      
        The content of the 
      <TEXTAREA> element is the field's initial value.
      
        Typically, the ROWS and COLS attributes determine the visible
        dimension of the field in characters. The field is typically rendered
        in a fixed-width font. HTML user agents should allow text to extend
        beyond these limits by scrolling as needed.
      
      8.2. Form Submission
      
        An HTML user agent begins processing a form by presenting the
        document with the fields in their initial state. The user is allowed
        to modify the fields, constrained by the field type etc.  When the
        user indicates that the form should be submitted (using a submit
        button or image input), the form data set is processed according to
        its method, action URI and enctype.
      
      
      
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      RFC 1866            Hypertext Markup Language - 2.0        November 1995
      
      
        When there is only one single-line text input field in a form, the
        user agent should accept Enter in that field as a request to submit
        the form.
      
      8.2.1. The form-urlencoded Media Type
      
        The default encoding for all forms is `application/x-www-form-
        urlencoded'. A form data set is represented in this media type as
        follows:
      
        1. The form field names and values are escaped: space
        characters are replaced by `+', and then reserved characters
        are escaped as per [URL]; that is, non-alphanumeric
        characters are replaced by `%HH', a percent sign and two
        hexadecimal digits representing the ASCII code of the
        character. Line breaks, as in multi-line text field values,
        are represented as CR LF pairs, i.e. `%0D%0A'.
      
        2. The fields are listed in the order they appear in the
        document with the name separated from the value by `=' and
        the pairs separated from each other by `&amp;''. Fields with null
        values may be omitted. In particular, unselected radio
        buttons and checkboxes should not appear in the encoded
        data, but hidden fields with VALUE attributes present
        should.
      
         NOTE - The URI from a query form submission can be
         used in a normal anchor style hyperlink.
         Unfortunately, the use of the `&amp;'' character to
         separate form fields interacts with its use in SGML
         attribute values as an entity reference delimiter.
         For example, the URI `http://host/?x=1&amp;y=2' must be
         written `&lt;a href="http://host/?x=1&amp;y=2"' or `&lt;a
         href="http://host/?x=1&amp;y=2"&gt;'.
      
         HTTP server implementors, and in particular, CGI
         implementors are encouraged to support the use of
         `;' in place of `&amp;'' to save users the trouble of
         escaping `&amp;'' characters this way.
      
      8.2.2. Query Forms: METHOD=GET
      
        If the processing of a form is idempotent (i.e. it has no lasting
        observable effect on the state of the world), then the form method
        should be `GET'. Many database searches have no visible side-effects
        and make ideal applications of query forms.
      
      
      
      
      
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      RFC 1866            Hypertext Markup Language - 2.0        November 1995
      
      
        To process a form whose action URL is an HTTP URL and whose method is
        `GET', the user agent starts with the action URI and appends a `?'
        and the form data set, in `application/x-www-form-urlencoded' format
        as above. The user agent then traverses the link to this URI just as
        if it were an anchor (see 7.2, "Activation of Hyperlinks").
      
      NOTE - The URL encoding may result in very long URIs, which cause
      some historical HTTP server implementations to exhibit defective
      behavior. As a result, some HTML forms are written using
      `METHOD=POST' even though the form submission has no side-effects.
      
      8.2.3. Forms with Side-Effects: METHOD=POST
      
        If the service associated with the processing of a form has side
        effects (for example, modification of a database or subscription to a
        service), the method should be `POST'.
      
        To process a form whose action URL is an HTTP URL and whose method is
        `POST', the user agent conducts an HTTP POST transaction using the
        action URI, and a message body of type `application/x-www-form-
        urlencoded' format as above. The user agent should display the
        response from the HTTP POST interaction just as it would display the
        response from an HTTP GET above.
      
      8.2.4. Example Form Submission: Questionnaire Form
      
        Consider the following document:
      
        &lt;!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN"&gt;
        &lt;title&gt;Sample of HTML Form Submission&lt;/title&gt;
        &lt;H1&gt;Sample Questionnaire&lt;/H1&gt;
        &lt;P&gt;Please fill out this questionnaire:
        &lt;FORM METHOD="POST" ACTION="http://www.w3.org/sample"&gt;
        &lt;P&gt;Your name: &lt;INPUT NAME="name" size="48"&gt;
        &lt;P&gt;Male &lt;INPUT NAME="gender" TYPE=RADIO VALUE="male"&gt;
        &lt;P&gt;Female &lt;INPUT NAME="gender" TYPE=RADIO VALUE="female"&gt;
        &lt;P&gt;Number in family: &lt;INPUT NAME="family" TYPE=text&gt;
        &lt;P&gt;Cities in which you maintain a residence:
        &lt;UL&gt;
        &lt;LI&gt;Kent &lt;INPUT NAME="city" TYPE=checkbox VALUE="kent"&gt;
        &lt;LI&gt;Miami &lt;INPUT NAME="city" TYPE=checkbox VALUE="miami"&gt;
        &lt;LI&gt;Other &lt;TEXTAREA NAME="other" cols=48 rows=4&gt;</TEXTAREA>
        Nickname: 
      <INPUT NAME="nickname" SIZE="42"/>
      <P>Thank you for responding to this questionnaire.</P>
      <P>
        <INPUT TYPE="SUBMIT"/>
        <INPUT TYPE="RESET"/>
      </P>
    </FORM>
    Introduction to HTML
    <p>
       element and a 
      Some text. 
      <em>*wow*</em>
    </p>
    Network Working Group                                    T. Berners-Lee
    Request for Comments: 1866                                      MIT/W3C
    Category: Standards Track                                   D. Connolly
        November 1995
    
    
       Hypertext Markup Language - 2.0
    
    Status of this Memo
    
     This document specifies an Internet standards track protocol for the
     Internet community, and requests discussion and suggestions for
     improvements.  Please refer to the current edition of the "Internet
     Official Protocol Standards" (STD 1) for the standardization state
     and status of this protocol.  Distribution of this memo is unlimited.
    
    Abstract
    
     The Hypertext Markup Language (HTML) is a simple markup language used
     to create hypertext documents that are platform independent. HTML
     documents are SGML documents with generic semantics that are
     appropriate for representing information from a wide range of
     domains. HTML markup can represent hypertext news, mail,
     documentation, and hypermedia; menus of options; database query
     results; simple structured documents with in-lined graphics; and
     hypertext views of existing bodies of information.
    
     HTML has been in use by the World Wide Web (WWW) global information
     initiative since 1990. This specification roughly corresponds to the
     capabilities of HTML in common use prior to June 1994. HTML is an
     application of ISO Standard 8879:1986 Information Processing Text and
     Office Systems; Standard Generalized Markup Language (SGML).
    
     The "text/html" Internet Media Type (RFC 1590) and MIME Content Type
     (RFC 1521) is defined by this specification.
    
    Table of Contents
    
    1.     Introduction ........................................... 2
    1.1    Scope .................................................. 3
    1.2    Conformance ............................................ 3
    2.     Terms .................................................. 6
    3.     HTML as an Application of SGML .........................10
    3.1    SGML Documents .........................................10
    3.2    HTML Lexical Syntax ................................... 12
    3.3    HTML Public Text Identifiers .......................... 17
    3.4    Example HTML Document ................................. 17
    4.     HTML as an Internet Media Type ........................ 18
    
    
    
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    RFC 1866            Hypertext Markup Language - 2.0        November 1995
    
    
    4.1    text/html media type .................................. 18
    4.2    HTML Document Representation .......................... 19
    5.     Document Structure .................................... 20
    5.1    Document Element: HTML ................................ 21
    5.2    Head: HEAD ............................................ 21
    5.3    Body: BODY ............................................ 24
    5.4    Headings: H1 ... H6 ................................... 24
    5.5    Block Structuring Elements ............................ 25
    5.6    List Elements ......................................... 28
    5.7    Phrase Markup ......................................... 30
    5.8    Line Break: BR ........................................ 34
    5.9    Horizontal Rule: HR ................................... 34
    5.10   Image: IMG ............................................ 34
    6.     Characters, Words, and Paragraphs ..................... 35
    6.1    The HTML Document Character Set ....................... 36
    7.     Hyperlinks ............................................ 36
    7.1    Accessing Resources ................................... 37
    7.2    Activation of Hyperlinks .............................. 38
    7.3    Simultaneous Presentation of Image Resources .......... 38
    7.4    Fragment Identifiers .................................. 38
    7.5    Queries and Indexes ................................... 39
    7.6    Image Maps ............................................ 39
    8.     Forms ................................................. 40
    8.1    Form Elements ......................................... 40
    8.2    Form Submission ....................................... 45
    9.     HTML Public Text ...................................... 49
    9.1    HTML DTD .............................................. 49
    9.2    Strict HTML DTD ....................................... 61
    9.3    Level 1 HTML DTD ...................................... 62
    9.4    Strict Level 1 HTML DTD ............................... 63
    9.5    SGML Declaration for HTML ............................. 64
    9.6    Sample SGML Open Entity Catalog for HTML .............. 65
    9.7    Character Entity Sets ................................. 66
    10.    Security Considerations ............................... 69
    11.    References ............................................ 69
    12.    Acknowledgments ....................................... 71
    12.1   Authors' Addresses .................................... 71
    13.    The HTML Coded Character Set .......................... 72
    14.    Proposed Entities ..................................... 75
    
    1. Introduction
    
     The HyperText Markup Language (HTML) is a simple data format used to
     create hypertext documents that are portable from one platform to
     another. HTML documents are SGML documents with generic semantics
     that are appropriate for representing information from a wide range
     of domains.
    
    
    
    
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     As HTML is an application of SGML, this specification assumes a
     working knowledge of [SGML].
    
    1.1. Scope
    
     HTML has been in use by the World-Wide Web (WWW) global information
     initiative since 1990. Previously, informal documentation on HTML has
     been available from a number of sources on the Internet. This
     specification brings together, clarifies, and formalizes a set of
     features that roughly corresponds to the capabilities of HTML in
     common use prior to June 1994. A number of new features to HTML are
     being proposed and experimented in the Internet community.
    
     This document thus defines a HTML 2.0 (to distinguish it from the
     previous informal specifications). Future (generally upwardly
     compatible) versions of HTML with new features will be released with
     higher version numbers.
    
     HTML is an application of ISO Standard 8879:1986, "Information
     Processing Text and Office Systems; Standard Generalized Markup
     Language" (SGML). The HTML Document Type Definition (DTD) is a formal
     definition of the HTML syntax in terms of SGML.
    
     This specification also defines HTML as an Internet Media
     Type[IMEDIA] and MIME Content Type[MIME] called `text/html'. As such,
     it defines the semantics of the HTML syntax and how that syntax
     should be interpreted by user agents.
    
    1.2. Conformance
    
     This specification governs the syntax of HTML documents and aspects
     of the behavior of HTML user agents.
    
    1.2.1. Documents
    
     A document is a conforming HTML document if:
    
      * It is a conforming SGML document, and it conforms to the
      HTML DTD (see 9.1, "HTML DTD").
    
       NOTE - There are a number of syntactic idioms that
       are not supported or are supported inconsistently in
       some historical user agent implementations. These
       idioms are identified in notes like this throughout
       this specification.
    
      * It conforms to the application conventions in this
      specification. For example, the value of the HREF attribute
    
    
    
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      of the 
    <A> element must conform to the URI syntax.
    
      * Its document character set includes [ISO-8859-1] and
      agrees with [ISO-10646]; that is, each code position listed
      in 13, "The HTML Coded Character Set" is included, and each
      code position in the document character set is mapped to the
      same character as [ISO-10646] designates for that code
      position.
    
       NOTE - The document character set is somewhat
       independent of the character encoding scheme used to
       represent a document. For example, the `ISO-2022-JP'
       character encoding scheme can be used for HTML
       documents, since its repertoire is a subset of the
       [ISO-10646] repertoire. The critical distinction is
       that numeric character references agree with
       [ISO-10646] regardless of how the document is
       encoded.
    
    1.2.2. Feature Test Entities
    
     The HTML DTD defines a standard HTML document type and several
     variations, by way of feature test entities. Feature test entities
     are declarations in the HTML DTD that control the inclusion or
     exclusion of portions of the DTD.
    
    HTML.Recommended
       Certain features of the language are necessary for
       compatibility with widespread usage, but they may
       compromise the structural integrity of a document. This
       feature test entity selects a more prescriptive document
       type definition that eliminates those features. It is
       set to `IGNORE' by default.
    
       For example, in order to preserve the structure of a
       document, an editing user agent may translate HTML
       documents to the recommended subset, or it may require
       that the documents be in the recommended subset for
       import.
    
    HTML.Deprecated
       Certain features of the language are necessary for
       compatibility with earlier versions of the
       specification, but they tend to be used and implemented
       inconsistently, and their use is deprecated. This
       feature test entity enables a document type definition
       that allows these features. It is set to `INCLUDE' by
       default.
    
    
    
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       Documents generated by translation software or editing
       software should not contain deprecated idioms.
    
    1.2.3. User Agents
    
     An HTML user agent conforms to this specification if:
    
      * It parses the characters of an HTML document into data
      characters and markup according to [SGML].
    
       NOTE - In the interest of robustness and
       extensibility, there are a number of widely deployed
       conventions for handling non-conforming documents.
       See 4.2.1, "Undeclared Markup Error Handling" for
       details.
    
      * It supports the `ISO-8859-1' character encoding scheme and
      processes each character in the ISO Latin Alphabet No. 1 as
      specified in 6.1, "The HTML Document Character Set".
    
       NOTE - To support non-western writing systems, HTML
       user agents are encouraged to support
       `ISO-10646-UCS-2' or similar character encoding
       schemes and as much of the character repertoire of
       [ISO-10646] as is practical.
    
      * It behaves identically for documents whose parsed token
      sequences are identical.
    
      For example, comments and the whitespace in tags disappear
      during tokenization, and hence they do not influence the
      behavior of conforming user agents.
    
      * It allows the user to traverse (or at least attempt to
      traverse, resources permitting) all hyperlinks from </A>
    <A>
      elements in an HTML document.
    
     An HTML user agent is a level 2 user agent if, additionally:
    
      * It allows the user to express all form field values
      specified in an HTML document and to (attempt to) submit the
      values as requests to information services.
    
    
    
    
    
    
    
    
    
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    2. Terms
    
    absolute URI
       a URI in absolute form; for example, as per [URL]
    
    anchor
       one of two ends of a hyperlink; typically, a phrase
       marked as an </A>
    <A>
       element.
      
        base URI
         an absolute URI used in combination with a relative URI
         to determine another absolute URI.
      
        character
         An atom of information, for example a letter or a digit.
         Graphic characters have associated glyphs, whereas
         control characters have associated processing semantics.
      
        character encoding
        scheme
         A function whose domain is the set of sequences of
         octets, and whose range is the set of sequences of
         characters from a character repertoire; that is, a
         sequence of octets and a character encoding scheme
         determines a sequence of characters.
      
        character repertoire
         A finite set of characters; e.g. the range of a coded
         character set.
      
        code position
         An integer. A coded character set and a code position
         from its domain determine a character.
      
        coded character set
         A function whose domain is a subset of the integers and
         whose range is a character repertoire. That is, for some
         set of integers (usually of the form {0, 1, 2, ..., N}
         ), a coded character set and an integer in that set
         determine a character. Conversely, a character and a
         coded character set determine the character's code
         position (or, in rare cases, a few code positions).
      
        conforming HTML user
        agent
         A user agent that conforms to this specification in its
         processing of the Internet Media Type `text/html'.
      
      
      
      
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        data character
         Characters other than markup, which make up the content
         of elements.
      
        document character set
         a coded character set whose range includes all
         characters used in a document. Every SGML document has
         exactly one document character set. Numeric character
         references are resolved via the document character set.
      
        DTD
         document type definition. Rules that apply SGML to the
         markup of documents of a particular type, including a
         set of element and entity declarations. [SGML]
      
        element
         A component of the hierarchical structure defined by a
         document type definition; it is identified in a document
         instance by descriptive markup, usually a start-tag and
         end-tag. [SGML]
      
        end-tag
         Descriptive markup that identifies the end of an
         element. [SGML]
      
        entity
         data with an associated notation or interpretation; for
         example, a sequence of octets associated with an
         Internet Media Type. [SGML]
      
        fragment identifier
         the portion of an HREF attribute value following the `#'
         character which modifies the presentation of the
         destination of a hyperlink.
      
        form data set
         a sequence of name/value pairs; the names are given by
         an HTML document and the values are given by a user.
      
        HTML document
         An SGML document conforming to this document type
         definition.
      
        hyperlink
         a relationship between two anchors, called the head and
         the tail. The link goes from the tail to the head. The
         head and tail are also known as destination and source,
         respectively.
      
      
      
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        markup
         Syntactically delimited characters added to the data of
         a document to represent its structure. There are four
         different kinds of markup: descriptive markup (tags),
         references, markup declarations, and processing
         instructions. [SGML]
      
        may
         A document or user interface is conforming whether this
         statement applies or not.
      
        media type
         an Internet Media Type, as per [IMEDIA].
      
        message entity
         a head and body. The head is a collection of name/value
         fields, and the body is a sequence of octets. The head
         defines the content type and content transfer encoding
         of the body. [MIME]
      
        minimally conforming
        HTML user agent
         A user agent that conforms to this specification except
         for form processing. It may only process level 1 HTML
         documents.
      
        must
         Documents or user agents in conflict with this statement
         are not conforming.
      
        numeric character
        reference
         markup that refers to a character by its code position
         in the document character set.
      
        SGML document
         A sequence of characters organized physically as a set
         of entities and logically into a hierarchy of elements.
         An SGML document consists of data characters and markup;
         the markup describes the structure of the information
         and an instance of that structure. [SGML]
      
        shall
         If a document or user agent conflicts with this
         statement, it does not conform to this specification.
      
      
      
      
      
      
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        should
         If a document or user agent conflicts with this
         statement, undesirable results may occur in practice
         even though it conforms to this specification.
      
        start-tag
         Descriptive markup that identifies the start of an
         element and specifies its generic identifier and
         attributes. [SGML]
      
        syntax-reference
        character set
         A coded character set whose range includes all
         characters used for markup; e.g. name characters and
         delimiter characters.
      
        tag
         Markup that delimits an element. A tag includes a name
         which refers to an element declaration in the DTD, and
         may include attributes. [SGML]
      
        text entity
         A finite sequence of characters. A text entity typically
         takes the form of a sequence of octets with some
         associated character encoding scheme, transmitted over
         the network or stored in a file. [SGML]
      
        typical
         Typical processing is described for many elements. This
         is not a mandatory part of the specification but is
         given as guidance for designers and to help explain the
         uses for which the elements were intended.
      
        URI
         A Uniform Resource Identifier is a formatted string that
         serves as an identifier for a resource, typically on the
         Internet. URIs are used in HTML to identify the anchors
         of hyperlinks. URIs in common practice include Uniform
         Resource Locators (URLs)[URL] and Relative URLs
         [RELURL].
      
        user agent
         A component of a distributed system that presents an
         interface and processes requests on behalf of a user;
         for example, a www browser or a mail user agent.
      
      
      
      
      
      
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        WWW
         The World-Wide Web is a hypertext-based, distributed
         information system created by researchers at CERN in
         Switzerland. 
      <URL:http www.w3.org=""></URL:http>
      
      3. HTML as an Application of SGML
      
        HTML is an application of ISO 8879:1986 -- Standard Generalized
        Markup Language (SGML). SGML is a system for defining structured
        document types and markup languages to represent instances of those
        document types[SGML]. The public text -- DTD and SGML declaration --
        of the HTML document type definition are provided in 9, "HTML Public
        Text".
      
        The term "HTML" refers to both the document type defined here and the
        markup language for representing instances of this document type.
      
      3.1. SGML Documents
      
        An HTML document is an SGML document; that is, a sequence of
        characters organized physically into a set of entities, and logically
        as a hierarchy of elements.
      
        In the SGML specification, the first production of the SGML syntax
        grammar separates an SGML document into three parts: an SGML
        declaration, a prologue, and an instance. For the purposes of this
        specification, the prologue is a DTD. This DTD describes another
        grammar: the start symbol is given in the doctype declaration, the
        terminals are data characters and tags, and the productions are
        determined by the element declarations. The instance must conform to
        the DTD, that is, it must be in the language defined by this grammar.
      
        The SGML declaration determines the lexicon of the grammar. It
        specifies the document character set, which determines a character
        repertoire that contains all characters that occur in all text
        entities in the document, and the code positions associated with
        those characters.
      
        The SGML declaration also specifies the syntax-reference character
        set of the document, and a few other parameters that bind the
        abstract syntax of SGML to a concrete syntax. This concrete syntax
        determines how the sequence of characters of the document is mapped
        to a sequence of terminals in the grammar of the prologue.
      
      
      
      
      
      
      
      
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        For example, consider the following document:
      
        &lt;!DOCTYPE html PUBLIC "-//IETF//DTD HTML 2.0//EN"&gt;
      
        An HTML user agent should use the SGML declaration that is given in
        9.5, "SGML Declaration for HTML". According to its document character
        set, `*' refers to an asterisk character, `*'.
      
        The instance above is regarded as the following sequence of
        terminals:
      
        1. start-tag: TITLE
      
        2. data characters: "Parsing Example"
      
        3. end-tag: TITLE
      
        4. start-tag: P
      
        5. data characters "Some text."
      
        6. start-tag: EM
      
        7. data characters: "*wow*"
      
        8. end-tag: EM
      
        9. end-tag: P
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
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        The start symbol of the DTD grammar is HTML, and the productions are
        given in the public text identified by `-//IETF//DTD HTML 2.0//EN'
        (9.1, "HTML DTD"). The terminals above parse as:
      
       HTML
        |
        \-HEAD
        |  |
        |  \-TITLE
        |      |
        |      \-
        |      |
        |      \-"Parsing Example"
        |      |
        |      \-
        |
        \-BODY
          |
          \-P
         |
         \-
      
        Some of the elements are delimited explicitly by tags, while the
        boundaries of others are inferred. The 
       element contains a
      
      4. HTML as an Internet Media Type
      
        An HTML user agent allows users to interact with resources which have
        HTML representations. At a minimum, it must allow users to examine
        and navigate the content of HTML level 1 documents. HTML user agents
        should be able to preserve all formatting distinctions represented in
        an HTML document, and be able to simultaneously present resources
        referred to by IMG elements (they may ignore some formatting
        distinctions or IMG resources at the request of the user). Level 2
        HTML user agents should support form entry and submission.
      
      4.1. text/html media type
      
        This specification defines the Internet Media Type [IMEDIA] (formerly
        referred to as the Content Type [MIME]) called `text/html'. The
        following is to be registered with [IANA].
      
        Media Type name
         text
      
        Media subtype name
         html
      
        Required parameters
         none
      
      
      
      
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        Optional parameters
         level, charset
      
        Encoding considerations
         any encoding is allowed
      
        Security considerations
         see 10, "Security Considerations"
      
        The optional parameters are defined as follows:
      
        Level
         The level parameter specifies the feature set used in
         the document. The level is an integer number, implying
         that any features of same or lower level may be present
         in the document. Level 1 is all features defined in this
         specification except those that require the 
    </A>
    <FORM>
         element. Level 2 includes form processing. Level 2 is
         the default.
      
        Charset
         The charset parameter (as defined in section 7.1.1 of
         RFC 1521[MIME]) may be given to specify the character
         encoding scheme used to represent the HTML document as a
         sequence of octets. The default value is outside the
         scope of this specification; but for example, the
         default is `US-ASCII' in the context of MIME mail, and
         `ISO-8859-1' in the context of HTTP [HTTP].
      
      4.2. HTML Document Representation
      
        A message entity with a content type of `text/html' represents an
        HTML document, consisting of a single text entity. The `charset'
        parameter (whether implicit or explicit) identifies a character
        encoding scheme. The text entity consists of the characters
        determined by this character encoding scheme and the octets of the
        body of the message entity.
      
      4.2.1. Undeclared Markup Error Handling
      
        To facilitate experimentation and interoperability between
        implementations of various versions of HTML, the installed base of
        HTML user agents supports a superset of the HTML 2.0 language by
        reducing it to HTML 2.0: markup in the form of a start-tag or end-
        tag, whose generic identifier is not declared is mapped to nothing
        during tokenization. Undeclared attributes are treated similarly. The
        entire attribute specification of an unknown attribute (i.e., the
        unknown attribute and its value, if any) should be ignored. On the
      
      
      
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        other hand, references to undeclared entities should be treated as
        data characters.
      
        For example:
      
      <div class="chapter">
        <h1>foo</h1>
        <p>...</p>
      </div>
      =&gt; 
      <H1>,"foo",</H1>
      ,
      <P>,"..."
        xxx </P>
      <P ID="z23"> yyy
      =&gt; "xxx ",</P>
      <P>," yyy
        Let α &amp; β be finite sets.
      =&gt; "Let α &amp;  β be finite sets."
      
        Support for notifying the user of such errors is encouraged.
      
        Information providers are warned that this convention is not binding:
        unspecified behavior may result, as such markup does not conform to
        this specification.
      
      4.2.2. Conventional Representation of Newlines
      
        SGML specifies that a text entity is a sequence of records, each
        beginning with a record start character and ending with a record end
        character (code positions 10 and 13 respectively) (section 7.6.1,
        "Record Boundaries" in [SGML]).
      
        [MIME] specifies that a body of type `text/*' is a sequence of lines,
        each terminated by CRLF, that is, octets 13, 10.
      
        In practice, HTML documents are frequently represented and
        transmitted using an end of line convention that depends on the
        conventions of the source of the document; frequently, that
        representation consists of CR only, LF only, or a CR LF sequence.
        Hence the decoding of the octets will often result in a text entity
        with some missing record start and record end characters.
      
        Since there is no ambiguity, HTML user agents are encouraged to infer
        the missing record start and end characters.
      
        An HTML user agent should treat end of line in any of its variations
        as a word space in all contexts except preformatted text. Within
        preformatted text, an HTML user agent should treat any of the three
        common representations of end-of-line as starting a new line.
      
      5. Document Structure
      
        An HTML document is a tree of elements, including a head and body,
        headings, paragraphs, lists, etc. Form elements are discussed in 8,
        "Forms".
      
      
      
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      5.1. Document Element: HTML
      
        The HTML document element consists of a head and a body, much like a
        memo or a mail message. The head contains the title and optional
        elements. The body is a text flow consisting of paragraphs, lists,
        and other elements.
      
      5.2. Head: HEAD
      
        The head of an HTML document is an unordered collection of
        information about the document. For example:
      
        &lt;!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN"&gt;</P>
        ...
      
      5.2.1. Title: TITLE
      
        Every HTML document must contain a 
    </FORM>
    <P>
         |
         \-"Some text. "
         |
         \-EM
         |  |
         |  \-
      <EM>
         |  |
         |  \-"*wow*"
         |  |
         |  \-</EM>
         |
         \-
    </P>
     element. The 
     contains 
    ,
     which is explicitly delimited by start- and end-tags.
    
    3.2. HTML Lexical Syntax
    
     SGML specifies an abstract syntax and a reference concrete syntax.
     Aside from certain quantities and capacities (e.g. the limit on the
     length of a name), all HTML documents use the reference concrete
     syntax. In particular, all markup characters are in the repertoire of
     [ISO-646]. Data characters are drawn from the document character set
     (see 6, "Characters, Words, and Paragraphs").
    
    
    
    
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     A complete discussion of SGML parsing, e.g. the mapping of a sequence
     of characters to a sequence of tags and data, is left to the SGML
     standard[SGML]. This section is only a summary.
    
    3.2.1. Data Characters
    
     Any sequence of characters that do not constitute markup (see 9.6
     "Delimiter Recognition" of [SGML]) are mapped directly to strings of
     data characters. Some markup also maps to data character strings.
     Numeric character references map to single-character strings, via the
     document character set. Each reference to one of the general entities
     defined in the HTML DTD maps to a single-character string.
    
     For example,
    
    abc&lt;def    =&gt; "abc","&lt;","def"
    abc&lt;def   =&gt; "abc","&lt;","def"
    
     The terminating semicolon on entity or numeric character references
     is only necessary when the character following the reference would
     otherwise be recognized as part of the name (see 9.4.5 "Reference
     End" in [SGML]).
    
    abc &lt; def     =&gt; "abc ","&lt;"," def"
    abc &lt; def    =&gt; "abc ","&lt;"," def"
    
     An ampersand is only recognized as markup when it is followed by a
     letter or a `#' and a digit:
    
    abc &amp;  lt def    =&gt; "abc &amp;  lt def"
    abc  60 def    =&gt; "abc  60 def"
    
     A useful technique for translating plain text to HTML is to replace
     each '&lt;', '&amp;'', and '&gt;' by an entity reference or numeric character
     reference as follows:
    
       ENTITY      NUMERIC
        CHARACTER REFERENCE   CHAR REF     CHARACTER DESCRIPTION
        --------- ----------  -----------  ---------------------
       &amp;        &amp;       &amp;        Ampersand
       &lt;       &lt;        &lt;        Less than
       &gt;       &gt;        &gt;        Greater than
    
      NOTE - There are SGML mechanisms, CDATA and RCDATA
      declared content, that allow most `&lt;', `&gt;', and `&amp;''
      characters to be entered without the use of entity
      references. Because these mechanisms tend to be used and
      implemented inconsistently, and because they conflict
    
    
    
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      with techniques for reducing HTML to 7 bit ASCII for
      transport, they are deprecated in this version of HTML.
      See 5.5.2.1, "Example and Listing: XMP, LISTING".
    
    3.2.2. Tags
    
     Tags delimit elements such as headings, paragraphs, lists, character
     highlighting, and links. Most HTML elements are identified in a
     document as a start-tag, which gives the element name and attributes,
     followed by the content, followed by the end tag. Start-tags are
     delimited by `&lt;' and `&gt;'; end tags are delimited by `&lt;/' and `&gt;'. An
     example is:
    
     &lt;H1&gt;This is a Heading&lt;/H1&gt;
    
     Some elements only have a start-tag without an end-tag. For example,
     to create a line break, use the `&lt;BR&gt;' tag.  Additionally, the end
     tags of some other elements, such as Paragraph (`&lt;/P&gt;'), List Item
     (`&lt;/LI&gt;'), Definition Term (`&lt;/DT&gt;'), and Definition Description
     (`&lt;/DD&gt;') elements, may be omitted.
    
     The content of an element is a sequence of data character strings and
     nested elements. Some elements, such as anchors, cannot be nested.
     Anchors and character highlighting may be put inside other
     constructs. See the HTML DTD, 9.1, "HTML DTD" for full details.
    
      NOTE - The SGML declaration for HTML specifies SHORTTAG YES, which
      means that there are other valid syntaxes for tags, such as NET
      tags, `&lt;EM/.../'; empty start tags, `&lt;&gt;'; and empty end-tags,
      `&lt;/&gt;'. Until support for these idioms is widely deployed, their
      use is strongly discouraged.
    
    3.2.3. Names
    
     A name consists of a letter followed by letters, digits, periods, or
     hyphens. The length of a name is limited to 72 characters by the
     `NAMELEN' parameter in the SGML declaration for HTML, 9.5, "SGML
     Declaration for HTML". Element and attribute names are not case
     sensitive, but entity names are.  For example, `&lt;BLOCKQUOTE&gt;',
     `&lt;BlockQuote&gt;', and `&lt;blockquote&gt;' are equivalent, whereas `&amp;' is
     different from `&amp;AMP'.
    
     In a start-tag, the element name must immediately follow the tag open
     delimiter `&lt;'.
    
    
    
    
    
    
    
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    3.2.4. Attributes
    
     In a start-tag, white space and attributes are allowed between the
     element name and the closing delimiter. An attribute specification
     typically consists of an attribute name, an equal sign, and a value,
     though some attribute specifications may be just a name token. White
     space is allowed around the equal sign.
    
     The value of the attribute may be either:
    
      * A string literal, delimited by single quotes or double
      quotes and not containing any occurrences of the delimiting
      character.
    
       NOTE - Some historical implementations consider any
       occurrence of the `&gt;' character to signal the end of
       a tag. For compatibility with such implementations,
       when `&gt;' appears in an attribute value, it should be
       represented with a numeric character reference. For
       example, `&lt;IMG SRC="eq1.jpg" alt="a&gt;b"&gt;' should be
       written `&lt;IMG SRC="eq1.jpg" alt="a&gt;b"&gt;' or `&lt;IMG
       SRC="eq1.jpg" alt="a&gt;b"&gt;'.
    
      * A name token (a sequence of letters, digits, periods, or
      hyphens). Name tokens are not case sensitive.
    
       NOTE - Some historical implementations allow any
       character except space or `&gt;' in a name token.
    
     In this example, &lt;img&gt; is the element name, src is the attribute
     name, and `http://host/dir/file.gif' is the attribute value:
    
     &lt;img src='http://host/dir/file.gif'&gt;
    
     A useful technique for computing an attribute value literal for a
     given string is to replace each quote and white space character by an
     entity reference or numeric character reference as follows:
    
       ENTITY      NUMERIC
        CHARACTER REFERENCE   CHAR REF     CHARACTER DESCRIPTION
        --------- ----------  -----------  ---------------------
       HT                  	         Tab
       LF                  
      Line Feed
       CR                  
      Carriage Return
       SP                           Space
       "       "      "        Quotation mark
       &amp;        &amp;       &amp;        Ampersand
    
    
    
    
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    RFC 1866            Hypertext Markup Language - 2.0        November 1995
    
    
     For example:
    
     &lt;IMG SRC="image.jpg" alt="First "real" example"&gt;
    
     The `NAMELEN' parameter in the SGML declaration (9.5, "SGML
     Declaration for HTML") limits the length of an attribute value to
     1024 characters.
    
     Attributes such as ISMAP and COMPACT may be written using a minimized
     syntax (see 7.9.1.2 "Omitted Attribute Name" in [SGML]). The markup:
    
     &lt;UL COMPACT="compact"&gt;
    
     can be written using a minimized syntax:
    
     &lt;UL COMPACT&gt;
    
     NOTE - Some historical implementations only understand the minimized
     syntax.
    
    3.2.5. Comments
    
     To include comments in an HTML document, use a comment declaration. A
     comment declaration consists of `&lt;!' followed by zero or more
     comments followed by `&gt;'. Each comment starts with `--' and includes
     all text up to and including the next occurrence of `--'. In a
     comment declaration, white space is allowed after each comment, but
     not before the first comment.  The entire comment declaration is
     ignored.
    
      NOTE - Some historical HTML implementations incorrectly consider
      any `&gt;' character to be the termination of a comment.
    
     For example:
    
    &lt;!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN"&gt;
    &lt;HEAD&gt;
    &lt;TITLE&gt;HTML Comment Example
    <p>
      <!-- not a comment, just regular old data characters ->
      
      
      
      
      
      
      
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      3.3. HTML Public Text Identifiers
      
        To identify information as an HTML document conforming to this
        specification, each document must start with one of the following
        document type declarations.
      
        <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
      
        This document type declaration refers to the HTML DTD in 9.1, "HTML
        DTD".
      
      NOTE - If the body of a `text/html' message entity does not begin
      with a document type declaration, an HTML user agent should infer
      the above document type declaration.
      
        <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0 Level 2//EN">
      
        This document type declaration also refers to the HTML DTD which
        appears in 9.1, "HTML DTD".
      
        <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0 Level 1//EN">
      
        This document type declaration refers to the level 1 HTML DTD in 9.3,
        "Level 1 HTML DTD". Form elements must not occur in level 1
        documents.
      
        <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0 Strict//EN">
        <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0 Strict Level 1//EN">
      
        These two document type declarations refer to the HTML DTD in 9.2,
        "Strict HTML DTD" and 9.4, "Strict Level 1 HTML DTD". They refer to
        the more structurally rigid definition of HTML.
      
        HTML user agents may support other document types. In particular,
        they may support other formal public identifiers, or other document
        types altogether. They may support an internal declaration subset
        with supplemental entity, element, and other markup declarations.
      
      3.4. Example HTML Document
      
        <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
        <HTML>
        <! Here's a good place to put a comment. -->
    </p>
    Structural Example
    <H1>First Header</H1>
    <P>This is a paragraph in the example HTML file. Keep in mind
    
    
    
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    that the title does not appear in the document text, but that
    the header (defined by H1) does.</P>
    <OL>
      <LI>First item in an ordered list.</LI>
      <LI>
        Second item in an ordered list.
        <UL COMPACT="">
          <LI> Note that lists can be nested;</LI>
          <LI> Whitespace may be used to assist in reading the
           HTML source.</LI>
        </UL>
      </LI>
      <LI>Third item in an ordered list.</LI>
    </OL>
    <P>
      This is an additional paragraph. Technically, end tags are
        not required for paragraphs, although they are allowed. You can
        include character highlighting in a paragraph. 
      <EM>This sentence
        of the paragraph is emphasized.</EM>
       Note that the &lt;/P&gt;
        end tag has been omitted.
    </P>
    <P>
      <IMG SRC="triangle.xbm" alt="Warning: "/>
        Be sure to read these 
      <b>bold instructions</b>
      .
    </P>
  </BODY>
  <!-- Id: html-sgml.sgm,v 1.5 1995/05/26 21:29:50 connolly Exp  -->
  <!-- another   comment -->
  <!---->
</HTML>